Rotax reliability is now on par with the big bore cousins,Lycoming and continentals. i am just as confident behind a rotax as i am behind the IO540, even fly my own at cruise rpm of 5200rpm, keeping the revs higher keeps the internal pressures lower, runs smoother and never had a fault yet in just on 1000hrs behind it. i will fly behind jabs, and have flown them for quite some time, but i find myself a little more vigilant of potential landing areas when behind the jabiru.