I stayed at the Cassa last month and had mixed feelings about it. First of all, I thought the location was poor but I knew that going in. This might be a convenient location for tourists but it's way too close to Times Square for my liking (and therefore an absolute dead zone for good shopping/restaurants). Be prepared to walk at least 10 minutes in any direction to find some good places to eat and drink.
We were "upgraded" to a larger deluxe king on a high floor, but the room was very small (even by NYC hotel standards). There was barely enough room to fit a crib on the floor, and oddly they told me they only had 1 crib in the hotel available. The room was clean and very quiet though, and the bathroom was quite large relative to the room size.
Staff were excellent and very helpful with any requests. We also loved the balcony/lounge space they had. Was a great place to meet with friends and relax (BYOB).
There was a decent deli across the street (Cafe Manhattan) for breakfast (did not try Butter). Also found street parking on the W. 47th St., so didn't need to use the valet and that saved some $$$.
Overall this was a good use of 50k points/night and a free night certificate, but I wouldn't pay money to stay there given the location and small room size.