If you want to build pick up a SIG Kadet LT-40 kit, or if not you can get is an 'almost ready to fly'. Do a search for this plane on the boards here and you'll quickly see many people rate this as one of the best gas powered trainers. As for the Nexstar, i've seen mixed reviews. It seems that people are happy with it as a trainer although the "extras" it comes with are more of a gimmick than of real use, also seems to have a problem with its undercarriage coming loose.