By far, my favorite engine is the OS .40 LA. This little engine has lots of power to spare, turns over 18.000 RPMs, is very light, very quiet, never vibrates nor makes any weird noises, they last forever and if you have one of them and want to sell it, everyone will got nuts to get it.

Ok, lets cut the cr.., I enjoy my saitos .91 very much, probably the best engines I have owned. Among my engines I own or have owned are naturally saito 91, os70 4s KB65, tt46, tt42, os46fx, os15, os32sx, os25, os.10, kb40, os61fx, st45 and 61, os60fp and a few other.