I have never stayed in any of these hotels, so my advice is based on weddings, other visits to friends/associates staying in the hotel, etc.

The Four Seasons is a very laid back hotel. Nothing flashy at all (you might say plain), but very good service. It has a quiet ambiance that reminds me of their Washington, DC property.

Ritz Carlton does not look a hotel from the inside or the outside, but it is a stunning building. It has a gorgeous all dark wood Club Lounge with incredible views of the city. The largest suite, which occupies the entire top floor, is beautiful but actually feels a bit cramped. Beware that the standard rooms come in all shapes and sizes. Some do not have tubs.

The Rittenhouse has less of a hotel feel than that of a residential feel. I thought that the rooms were not as nicely decorated as the RC and that may be attributable to its age differential.

I would go for the Ritz or Four Seasons over the Rittenhouse. The Ritz is only a year or two old and is still working out some kinks in its dining venues and hotel service...but do not let that stop you from going there. The Four Seasons has no kinks to work out as the hotel service and dining there is excellent, but does not offer the eye-popping architecture of the RC. I would go to the FS unless I could fetch an RC Club room for a good price.