Any idea how much current you were drawing on 6s? I know they aren't that sexy but the HET fans are cheap and work. You can put about as much power as you want through them as well. If you want a 12s setup you could go with 700-68-1200 or probably better the 1125kv motor. It should be close to 9lbs of thrust per side. If the HET fans don't work the motors will also work in the Jetfan as well. The nose wheel is very sad looking
Good luck