RE: .25 Club Racing
The trouble with .25 powered quickies is usually on takeoff. They just don't swing a big enough prop to pull the airplane through an accidental stall on takeoff. Speed wise, you are at around 90 mph for an average good .25, though 100 is possible with a good airframe design. Also, if you don't alway have a headwind on takeoff, so even more accidents happen.
You would be far better off with a 40 sized engine, and keep the speed down with prop restrictions, like using a 10-5 instead of a 9-6.
The HOB T-6 does fly well on .25's, but they like to snap roll on takeoff if very much rudder is used.