I have the 60 and its a blast. I pushed the rudder back three inches by extending the fuse, added an inch to the rudder, and added a dorsel fin from half way up vert. fin to about a third of the way up the fuse. A 120 in/oz pull-pull servo and it will do knife edge loops. This thing was easy to build and a lot of fun to fly. I'm modifying it again, adding spoilers!!!!