why not go with the GP 1/12 combat planes. i flew my spitfire on the OS 30 and the Saito 40. flew very scale like. a 9x7 on the OS and a 10x7 on the saito. I latter did some mods to the OS 30 with the car version cam, springs and carb. and would turn a 8x6 APC at 16,000 very close to the OS 25ax