4* 60 Engine
I have had 2 of them. With a .61, they are a good flying airplane. You need a .91. I yanked my TT.61 after the first weekend and went to a .91. I have had an OS .91FX and a Magnum .91XLS. Both are the same weight as the corresponding .61 and both give the plane good vertical. My present plane has the Magnum with a Performance Specialties Ultra Thrust muffler and it will rotate on breaking ground to straight up and go as long as you want. 14-6 APC prop.
Clip one rib off each side. Rolls better and you won't notice it on landing. Still floats.