My perception has always been that Sheraton has a big quality/consistency problem. There are great ones and terrible ones. FS Marriotts are pretty bland, but they're consistent and good at what they do.

I've always perceived as Renaissance as above a FS Marriott - sort of like Marriott's LM. A little artsy, better food/drink, etc.

I've never stayed in a Delta Hotel. I just booked my first one today, though, a two-bedroom suite for $130/nt in the Chicago suburbs. At that price point, I was assuming it was a truly entry-level limited-service brand, but I went to the Marriott site and forum here and see that it's considered a FS brand with regular elite benefits and all. That's encouraging, although I'm still not sure what exactly I'm getting. Website makes it appear to be a new hotel, but I can't be certain.

I stayed in the new Sheraton room at the Overland Park Sheraton a couple months ago. A full suite plus two regular rooms. The rooms were beautiful with lots of desk/counter space. The lounge was open on the weekend - Easter Sunday, even - and it had been nicely renovated as well. That's always been a pretty good Sheraton, and they're clearly investing in keeping it that way.