Hi!
From personal experience , both helping several newbies and having raced in Q-500 pylon with the Kyosho .40 engine (same as the ASP .40) the ASP .40 is one of the most powerful sport engines on the market today.
If its the new version that came along 5-7 years ago.
That engine can easily swing a 12x6 prop using 15% nitro. I was quite stunned when I first saw that a few years ago.
For a Q-500 racer a 10x6 RAM or Graupner Cam-prop is the best prop! The ASP .40 will swing those props att around 14600rpm using just 80/20 fuel and a Nova Rossi 4 or 4A glowplug (one head shim removed).
Using 10-15% nitro do not remove the head shim!

For a high winged trainer a 11x6,12x4 or 12x6 prop (APC, RAM or Graupner Cam-Prop) is more suitable (at sea level).
10x6,11x4 or 11x5 are too small props for a high winged trainer if best preformance is what you are looking for