During peak hours the Princeton club is very busy, but otherwise this is a good gym. The architecture is basically the layout of an aircraft hangar, but has a large number of each type of equipment. During the evenings, I didn't have much of a wait for equipment. The gym includes most of the "extra" amenities including an indoor track, volleyball/basketball courts, pool, childrens daycare and an ungodly number of tanning beds.
Membership at the UW gym is probably a better price deal if you're a student or staff there (which is probably at least a quarter of the population of Madison). Some of the local health plans offer cash back if you work out enough days per month (mine offered $100 back if you worked out 10+ days per month for 6 months). Needless to say, this is the closest I've ever been to a professional athelete.