The best rooms between the two at the RC (high floors, facing City Hall...simply amazing views and nice rooms w/interesting layouts).

The best service between the two is at the RC Club. You need to check to make sure it is open on the dates you are going. It's a great little Club room done up in dark woods that smell as good as they look.

The best lobby and public spaces are at the RC.

The best restaurant is at the FS.

On average....they are tied for rooms (this is the typical US pre-2000 FS build so beware that even suites can lack seperate showers and double sinks! and the RC has nicer, newer finishings but the avg room can be dark and sometimes lacks a tub!)

On average, the better service is at the FS.

So if you do just a little homework on your room assignment the RC Club is the clearly the best choice and I think most people who even bother to post in this forum are willing to that little amount of work ahead of time. If you just want to book and not think about, then consider the FS...though it is not so clear even then that it is in the FS' favor.