It's been a long time since I rode ultrasports, but when I replaced my last one it was with a GP4000. The difference was quite noticeable in terms of ride quality and speed. I'd even go so far as to say they last longer and get fewer flats too but I don't have any actual data to back that up.
If I was in the market for tires today, I'd probably buy a pair of GP5000s, but being the thrifty type, I stocked up on GP4000 and Pro4 when the prices were good and I still haven't worn through them yet.