I'm assuming that the 400mph figure quoted is actual speed. What would the "scale" speed come out to?? I'm not into models, so I can't tell about what the scale is of that particular plane. If it's a 1:20, that would make the scale speed 8000mph, or mach 10+ at sea level!!
All I know from watching that, is that you could lose that sucker real fast if you're not paying attention.