I have visited four. In order of preference

N Seoul Tower - S Korea
CN Tower - Canada
Le Royal Meridien - UAE
Radisson Shanghai - China

An architect friend of mine once described these as revolting restaurants. From my experience the label fits. I still remember splurging over 30 years ago at the top of the BT tower in London to receive an atrocious meal complete with canned peas. I suspect that it's improved since then, if it's still there, like many English restaurants.

I do recall having a decent meal many years ago at the Marriott Marquis on Times Square. I can't comment on value as an advertising rep paid for the meal back when I was worth being wined & dined.

I also remember as a child being at a revolving restaurant in my hometown of Edmonton, Alberta (at the top of the then Chateau Lacombe) and when it initially opened one revolution took only about 30 minutes. It was fun! They soon slowed it down.

Top of Vancouver on a clear day or night is spectacular (in my totally biased opinion) but the food could never measure up to the view. Still I've been there perhaps 3 times for dinner just for the view. Don't bother on a rainy day.

I recommend JJ Astor in Duluth, MN. It is on the 16th floor of the Radisson hotel downtown and was recently renovated. I've been there twice and really enjoyed the afforable food, friendly service, and on a bright summer day, the view of lift bridge and park point is very nice, especially when freighters are pulling in to port.

The food is nothing more than bar food but the revolving restaurant atop the Doubletree Hotel in Crystal City offers wonderful views of DC, the Pentagon and flights going into and out of DCA... There was a fun FT get-together there a few years ago...

Thanks to this thread I mentioned Giratorio to some friends and had the surprise of my day when they all got excited and said we should go...as a laugh.

Interestingly, and maybe because our expectations were SO low, it was a blast. We had great drinks and very good food with good service (a rarity in Chile). The bill was quite high, though.

The key, I suppose, is to go with friends.

But I can recommend it.

+1 on Times Sq. Marriott.

Also, just back from New Orleans. Would have liked to know about Carousel bar last week. So it goes....

Top of the World
 

In Las Vegas is very good. A little pricey but the view makes it worth it.

I have two that I would recommend:

1. JJ Astor in Duluth MN. Excellent menu and has new decor. The view is the best Duluth has to offer!!
2. Stratosphere in Vegas. You're paying for the view, but we enjoyed it with friends.

Summit Bar/Restaurant in Sydney
 

In addition to Sydney Tower, Sydney has a second revolving bar/restaurant called Summit. It's not as high, but still has amazing views, especially at sunset.

It's cheaper, a tad less touristy and I'd recommend going there for drinks rather than for dinner. Food and service is mediocre, but the cocktails are good.

Agree on the view but be sure you check the weather report before you go or you may see nothing but clouds. Lauterbrunnen Valley one of my favorite places. Visited for the fifth time last summer.

Years and years ago I went to one in Houston called The Spindletop. The food was ok - nothing special. I'm not sure if it's even around any more. Not sure which building it was housed in.

I have not done it. Last year there was such a thing forva few weeks in Rio de Janeiro, featuring a different local chef every night. It was a grand success. A couple friends who did it claimed it to be an excellent concept.

Many years ago I really liked Juno's Revolving Restaurant in Kowloon. My taste was I'll-developed then so I would not have known the difference, but I loved the view.

It no longer operates as a restaurant/bar, but I remember going to the buffet at the Crown Room atop the Fairmont Hotel tower in San Francisco.