I have been researching motor options and cams across this thread - great read.
it appears that the plane can take a wide variety of motors, from .60 2s to 1.50 4s, depending on your flying style. I've decided on a Laser 155 (uk made glow 4s) which compares with the OS120AX in weight and power, so it should be a good combo.
my 2nd choice would be a DLE20ra.