Hello; I used a pair of TT pro 46's i my DC3. those OS Wankel''s are over $400 each here. That could be why no one uses them around here. I bought Surpass 70's for that plane but they added too much weight to the plane, so I didn't use them in there. I built the plane with no dihedral (big mistake) because of the extreme taper of the wings. Don't do that, my plane flies very nervously, you can't take your eye off it for a second. I got about 7 flights on it now, but it's no fun to fly, so I just hung it up.