We have had good experiences at all 3 places, but you need to be prepared for what each place is.
San Angel Inn does not serve what a lot of places in the US are familiar with as mexican, so be aware that depending on the area you live in, it may not be what you expect. For us (from middle TN) it was not what we are used to, but we still enjoyed it. The atmosphere is really awesome.
Coral Reef tends to be a hit or miss if you read dining reviews. A lot of people say it's all about the atmosphere, but we had really great food, as do a lot of others. It is a great place to go to at least once, but we will probably go back sometime again.
LeCellier is my husband's favorite, but I have never been blown away by it. I'm not a big eater, so it's hard for me to find anything on their menu that appeals to me. On the other hand, DH loves going there and getting their steaks. Just realize that a little of the excitement about this place is just being able to get in!

Then, for some it's just another restaurant, and for others it's the most wonderful restaurant ever.
So bottom line, be prepared for each one, and choose the one that is the most appealing to you. I don't think you can go wrong with any of them if it's truly the experience you want.