I live in Utah, fly at about 4000 ft asl and my ZDZ 50 pulls my 15 pound Cap straight up forever - I am putting a DA 50 on a PW and I'm hoping for the same - the PW is a little heavier, 16.5 lbs. Some of the ZDZ's and BME's have had some troubles I think the ZDZ's had some piston fit problems and the BME's were ign related but I'm turnin a 22/10 Mejzlik around 6600 on the ground so if you're not in that ballpark you may want to send it back.....