a friend has the 66" Extra with a Magnum 91 but is waiting for some warmer weather to try it out, I am planning on getting the Sukhoi to put my Magnum 91 on when taxes get done. I have talked to someone who has the Sukhoi with a TT 91 and tells me it has plenty of power and the Magnum should do just fine, I had mine on a T-34 that was 9+ pounds and it flies it well, I would go with the TT if you are going to buy one of the 2 engines. It has some more power than the magnum but in my opinion either would do well.

Dauntae