Katana my RV6 G-PWUL
XP 360 FI, 3 blade constant speed MT prop.7ish US gal normally gets me about 150Kts but if I'm in a hurry 175kt cruise is ok. At MAUW I can get over 2000ft per min, on my own about 3000ft per min. My friend has an 8 and his is about 10kts faster. My friend went from a CTSW to the 8 and you would not prize him out of it now for love nor money.
As for cost of ownership, if you can it's worth every penny.