The .91 2c flew it very unrealisticly. With a 15-6 it had nearly unlimited vertical from take off. The .91 flys very realisticly though. The take off is actually faster with the fourstroke 10', due to the superior throttle responce of the fourstroke vs/ 15 ' for the two stroke (clean out from idleing). The four stroke can climb at 60 degrees from take off were the two stroke climbes out about 75 degree's. My 1.10 should climb out at 90 degree's though and sound right doing it with a scale prop 16-6. I am just not a two stroke guy.