I put in about 20 hours, so far it's reliable. I am not afraid of overheating on these RPMs.(no fan cooling) It consumes 5 liter/hour of fuel with WW HP2, 6l/h with AXP 11 which is smaller and faster wing. This motor doesn't really like under 3500 RPM, the fuel mixture is too rich at low revs because gap control. By the way it is a very smooth running engine in the optimal working area (over 4000 RPM). At full throttle it gives ~6-7m/s lift (scary with slow wing), but I mostly use it in 2500-4000 range.