I started with an Avistar with the 40LA. Very reliable motor. I only replaced the glowplug once in 6 months, but that was because of a "Wheels up, Rudder down" landing. I destroyed the Avistar trying to do things I wasn't ready to do. But the 40LA lives on, presently in a T34. A little short of power for the T34, but a great 2nd level trainer.