I have a mid 90`s 912UL (80HP) in my Vixen. I have put almost 200 hrs on it over the last 2years (300TT). I change oil every 50 hrs (Mobil MXT), check carb sync about the same time, never add oil between changes, move the needle valve for winter or summer operation,no oil/coolant leaks. Just a great, strong running engine in my opinion. I fly mostly of pavement (not many bush strips around here) so I am really happy with 1000 ft,/min and 115 ias and about 12 to 15 litres/hour on 87 mogas. It doesn`t get much better than that!
Have fun with it
Don