I have a Jett FIRE .50 on my dust and it is incredibly fast. I've had it for a year and a half now and I still shake when I fly it. I talked to Dub Jet himself and told him I wanted the fastest thing I could get for a Diamond Dust. The pipe he sent me is REALLY loud. I have to wear ear defenders when I start it up. The sound it makes when I bring it down the runway 5 feet up at full throttle is like nothing you have ever heard. This thing is like flying a missile around. I don't do any aerobatics with it. It's just to show off the speed! With a more docile engine, you could do some aerobatics. Mine flies for about two minutes on that 6oz tank, but that's full throttle the whole time. I wouldn't be surprised if I was hitting 200 mph in straight and level flight. I bring mine in at a 45 degree dive at full throttle and it HAS to be doing over 200. When I fly this thing, everybody else lands. I don't know if they want to watch, or if they're just scared. Somebody mentioned something about a pinhole in the monokote causing it to come off. This is true. Make sure you wrap the monokote AROUND the leading edge. One one of my first flights, I was doing a high speed pass and saw a flash of red and the plane was flying very funny. I landed and all of the monokote on top of the right wing was gone. If you're going to put a fast engine on, you must make sure that there are no monokote seams hanging out in the airstream! For launching, it's hard to get somebody to help me. I bring two sets of ear defenders for who ever helps me, but it blasts exhaust all over whoever is launching the plane for you. So, I just made a simple takeoff dolly. It's airborne in about 5 feet anyways. Sometimes, I just start the engine, prop it up on something like my field box at a 60 degree angle, stand back and hit full throttle and it goes like a bat out of hell straight up. About the speed of one of those little Estes rockets. Everybody loves that the best! You'll love this plane no matter what engine you put on it! Matt