I had a ModelTech Cap21 about 7 years ago, nice kit now out pf production. I built mine per the manual with an OS60. Came out a tad on the heavy side but flow great. I installed a pull pull rudder on mine. The plane would knife edge forever and I believe is possible of doing a knife edge loop if it had more power. Snap maneuvers were quite violent but recovered well. Keep your speed up when doing maneuvers as it well snap on you as mine did twice. The second time I totaled it. I had another one but sold it. Not because I didn't like it just too many kits. You should be able to find a fiberglass cowl for it. When the model was in production, Fiberglass Specialties made one for it but not now.