RE: J-3 Engine Choice?
I have flown the H9 J3 with my Saito FA-56. Flew great. If you are a "gentle" flyer (like me) the 56 is perfect. If you want to throw the J3 around in the sky, use the FA-82. A Saito twin cylinder 90TS or a 60T would be great is money is not an issue.