I flew the Lear 45 from Yuma to San Diego this morning. It's a great aircraft, but it has an odd quirk. I was flying it manually, had trimmed out straight and level, and every time that I went to external view to look at the aircraft (it was the first time that I had flown it in the sim) my elevator trim would go out of whack and the aircraft would start climbing.
As long as I stayed in the pilot's seat, no problem. She'd cruise along straight and level just as nice as you could ask. But one peek at the aircraft from external view, and you're gaining altitude fast, with the VSI pegged at the top of the scale.
Aside from that, the Lear is a real sweetheart!