Either the Jett 90L or OS 91FX with a tuned muffler installed will get you pleanty of speed. Both are light weight, and mount identically.

The plane is a bit draggy, but flys great. It seems to like a 12" prop, although the last one I flew we installed an 11x7.5 on... and it was pretty quick (no radar numbers, sorry) . It does not perform like a QM or F-1 ship, but can be made to move with the correct prop selection.

I'm not sure about the DF engine......they tend to need to turn much smaller props at much higher RPM. Plus, it might be hard to mount the full length pipe.