I really like my Rotax, seems most folks I have met who have experience with them like them too. To be fair though I also owned a plane with an O-200 and the fuel burn is only a gal or so more per hour and it could also burn mo-gas. In fact, sadly enough, I generally put mo-gas in my O-200 but only burn Avgas in the Rotax (ethanol worries for my tanks).