I know that Kau Kee is in all the tourist guides and places to go as evidenced by the long lines at peak hours, but it's still one of my favorites. Definitely a place I take visitors when they come to Hong Kong.
My favorite thing to get is the beef brisket soup noodle with e-mein. The brisket is tender enough without being chewy. The noodles are soft, and absorb the flavor of the soup very well.
For beef you also have options for different types of beef or even a beef brisket in clear soup without noodles. That is pricier at $100+ but I feel the flavor of the soup is different and the brisket actually tastes better, but for ease of ordering with others, we generally each just get our own soup noodles.
For noodles you also have various options, but trust me. The e-mein is the best. Period.
There is a curry beef brisket with noodles, which some of my friends like, but I personally find it a little to spicy for my taste (a little spicier than mild).
Service: They are quick and are able to memorize your order and tell the cooks in abbreviated slang to get your noodles made.
Ambiance: You generally have to share tables with others, which isn't a big deal for me. But also don't expect to hang around and sit there for a long time. They start cleaning up your dishes as you clean.
Overall, friendly servers, great food (best beef brisket I've had in Hong Kong), and reasonable prices.

The first time I came I wasn't overly impressed and was trying to figure out what all the hype was about. The first time I came, I had roast pork over rice and they added their sauce on top. I felt it was salty and quite fatty and generally I don't prefer having sauce on top of my roasted meats so it just didn't do much for me.
I was in the area for a doctor's appointment so I decided to try again. As I was browsing pictures beforehand, I was already salivating and super excited. This time I ordered the Roast Goose and BBQ Pork over rice ($57), and made sure to ask for no sauce. The worker there made sure to let me know that if I chose duck instead of goose it would only be $27, but I had already decided beforehand I wanted to try the goose. It was great that he warned everybody ordering the goose that they could get the combo with the duck for $27 (I think non-combos also cost the same at $27). I also got a soup, too.
Soup: I thought it tasted fine. Getting soup from Chinese restaurants always gives me that homemade nostalgic feeling. I would get the soup again.
Goose: I thought the goose tasted fine. To me, goose tastes like a meatier version of duck, but was fine for me. Personally may not be worth the $30 to change from duck to meat since I find them similar. For others apparently they know better than me and can taste more of a difference, so unless I feel like having a change of pace, I am fine with sticking with duck.
BBQ Pork: This is where the winner was. The pork was soooo juicy and very good flavor and level of sweetness. The edges were a bit charred, but in a good way that gave the BBQ Pork more flavor. The meat was a little fatty but I think it may have been needed so that the pork would be juicier.
I feel like I still have moments when I crave for that BBQ Pork. This is a big deal, because generally if I have the option at a roast meat place, I usually pick roast pork, but not in this case.
Tip: It does get quite crowded at lunch, so you may have to try a non-peak time to reduce the wait.

As with many of the restaurants in Harbour City, there was a wait for this place. You are free to leave your phone number and have them call you when your table is ready. We chose to sit nearby, and waited quite awhile, and after talking to the people there after about 45 minutes, we were able to get seated at a table that just left.

We ordered 3 dishes. Unfortunately, I can only remember 2 - the seafood pancake and the mixed meat combo dish. The pancake tasted very good and was a large portion for the 3 of us. It tasted even better adding some of the spicy flavor from one of our 6 banchan (complimentary dishes they give you) dishes. For the meat, there was the option to cook it ourselves or have them cook it. Since we were hungry, (and maybe a little lazy), we had them cook the meat for us. And tasted very good!

They have very good service and were attentive, and didn't rush us at all (probably another reason why the restaurant has a wait, but that's good for us when we are eating).

I came here for a group gathering. It's nice because there is a room in the back that can fit at least 3 people, and is set with a wraparound sofa and tables, along with tables at the center for those who are mingling/standing.

The Living Room has very nice decor that is suitable for after-work drinks or even a date due to the dim lighting. The drinks are more pricey than the average bar, but you are paying for the environment and experience. It's also nice, because the bar isn't too packed either, and allows people to sit in the lounge chairs or at the bar.

Good for: groups, dates

Met up with others on a Sat morning. There were several people here, but no issues finding seats. It's double the size I'd expected. My drink was made quickly, and tasted fine, so no issues there. We stayed for about 3 hours and there was no one rushing us or anything. And the volume level there is not loud so it's even find for some group studying/gathering.

It is also in a convenient location at Festival Walk - just two escalator flights up from the Kowloon Tong MTR station.

Good for: group gatherings, studying, coffee break

Came here for my second time recently. It was the afternoon so there was no wait, though the place was about half full. I decided to go for the glutinous rice balls (tong yuen/yuen tong) filled with peanut in a sweet potato liquid with chunks of sweet potato. The sweet potato was cooked well. The liquid wasn't too sweet. And most importantly, I reallllly enjoyed the glutinous rice balls. The peanut filling was verrrry flavorful.

Service was good as well. We chatted for quite awhile before we ordered and after our desserts came we chatted for awhile also, and they didn't rush us. Service was prompt, and it was a good experience.

Will definitely return!

We made reservations two weeks out. It was quite busy due to a Groupon promo. A friend and I ordered the set menu, which came with several items.

There were many pictures of celebrities who have eaten at the restaurant, and they also had some cute decorations there.1. Choice of 2 skewers (We did chicken skin and another one I can't remember) Great! - Literally the best I've had since I first had yakitori in Tokyo.2. Okonomiyaki - My friend enjoyed it much more than I did, but it was pretty flavorful. I'm just not as used to sweet dishes (in this case, slight sweetness from the sauce). We also added ramen, which was added to the bottom of the okonomiyaki and was all fried and it was nice and crispy.3. Duck liver - Yum! Nice and smoky taste.4. Dessert - Sticky jelly texture with red bean filling in one of them and green tea in the otherIn addition, we also ordered some wings from the menu. They were called 3-flavor wings. They had seasoned the wings so different parts had a different flavor. I believe I tasted seaweed, spiciness, and I can't remember the last one now.The restaurant is relatively small and though there weren't too many people in the restaurant at the time we were eating, we were sitting very close to the table next to us, practically like we were sharing a table. I guess the food is good, and to serve more people the restaurant tries to fit as many there as possible. It did get busy later, so I guess they had saved reservations/Groupons at certain tables beforehand.

I made reservations the day of for a party of 5 with no problems. The 5 of us were actually given a private room to ourselves. What VIP service!

They didn't give us a time limit, but being in the room it was more difficult to get service for sauces, ordering, and the bill.

There were many broth options so we got a half/half broth with pork broth and a tomato broth. The tomato broth had a unique flavor, slightly sweet. I personally preferred the pork broth more.

Something unique that this Tanyoto does that I haven't seen at other hot pot places is they have a premixed bowl of ingredients for your sauce that has cilantro, hot sauce, and a few other things. Then when the broth arrives they ask you which broth you would like for your sauce and they add it to the bowl for you to dip your food in. I personally didn't like that there was so much cilantro. Separately we order two sauces - Satay Sauce and soy sauce. The sauces were $10 each. We didn't realize that the soy sauce also cost $10(!!) until after we ordered it, though it did seem to be a special one, as it didn't taste like regular soy sauce one would have at home.

The portion size of the ingredients was good, and tasted fresh.

I particularly enjoyed the frozen tofu, lamb, and fatty beef.

It was a Friday, and we ate at about 7:30pm/8p. I was told that after 9pm it was all you can eat, which would be a good deal if you could wait until later for dinner. Not sure about the cost for all you can eat, though.

Disclaimer: The restaurant isn't actually on Johnston Street as the address indicates. (Good thing my friend had been before, or else we would have been a-searchin'!) By MTR, when you come out of Wanchai A3 exit, turn left and walk to the corner and cross the street. Cross the street and the restaurant is about 2 stores to your left. There is an opening with a podium right inside. You are actually on the street perpendicular to Johnston - sorry, there is no street name on Google Maps. On Google Maps, it is shown there as Tan Yu Tou, right next to the Tung Hing Building.

We had previously made reservations, so there wasn't a problem getting seats, but it was a testament to the popularity of the place due to the large number of people waiting for seats outside.

Based on a friend's recommendation, we came here, and I was definitely not disappointed and actually pleasantly surprised how good it was. Usually, I'm not a big fan of udon and it never has tasted super special to me, but this time the broth was very good. I had the udon with pork in a shrimp broth! My first for a shrimp broth! When the noodles arrived it already smelled very shrimpy, in a good way, and tasted great as well.

The service was attentive and the prices were reasonable. The others in my party thoroughly enjoyed their meals as well.

I highly recommend making reservations if you can!

We were there early on a Saturday night with reservations for 6pm since we were heading to a movie after. We got the house special chicken that many people mentioned, and the crispy skin on the chicken was very good! It's not like any other chicken I had before. We also got a salt and pepper calamari/squid and that was also very flavorful. Lastly, we got the green beans, and that was yummy as well. The 3 plates for 3 of us with a couple bowls of rice were perfect portions, and the food came very quickly as well.

Since we were there early it was fine, but as we were leaving around 7pm we could see the restaurant start to fill up so I would recommend going earlier rather than later.

I will need to find another opportunity to return and have some more of that yummy chicken.

Recommended food: House special Chicken, Salt/Pepper Calamari