I have this model with a .90 2-stroke fitted. It cannot be flown flat out as it gets worryingly fast, however having said that I feel the power reserve is desireable for good acceleration from low speed.

If I were in your position, I think I'd prefer a 1.20 sized Four Stroke. There's no doubt that my P-47 has more than enough power, but I have already rejected the idea of fitting a smaller engine.

On times when the 90 has run poorly the performance becomes marginal very quickly. I'd much rather fly around at 1/2 throttle than be struggling around on the minimum specified power. Just my 2p...

If cost is a concern, then personally I'd spend the money on a good 90 sized 2 stroke (eg OS) rather than a buy a budget 4-stroke.

P-47s don't glide well so you don't want to be having too many dead sticks - treat budget engines with caution, and perhaps fly them in something less valuable/more forgiving first to prove them?