Yes, the new engine and prop will be worthwhile, especially since the CW-21 is basically an engine with a little aluminum tagging along behind it!

Though there is no resemblance, this little fighter reminds me of the Gee Bee racers--all engine and no airplane.
It pays to have the RTV and resin handy for short-run kits like these. In fact, I removed the propeller and spinner from a completed SBD so I could make these molds.