Never thought of the [link=http://www.mecoa.com/kb/aero/aircraft.htm]K&B[/link]. but i'm going to now! Click the [link=http://www.mecoa.com/kb/aero/aircraft.htm]K&B[/link] link for info. on them.I, as long as most are happy with there K&B, might just go with this engine. The 6150 is lighter than the OS-46FX by about 2oz. and has .28 more bhp. The 6150 is about 13oz lighter than the ST-75 and only has .13 less bhp. My goal is to get my 46 Sukhoi to have ULV (unlimited verticle) and great mid-range power. As it is right now with the OS engine i feel like the thing is going to fall out of the sky or slip sideways on takeoffs.