Bread is cheaper and it is biodegradeable, if either of those things matter.
Kevin stated the flaw in either/all "back pressure" techniques - a really worn (wallowed out) bushing might not allow enough back-pressure to push out the bushing.
I dimly recall once using a pilot bearing/bushing puller (search the Internet), but it must be able to fit in the relatively small hole in the bushing (1/2" - Jerry suggests 5/8"?).
Jerry's tap technique sound real good. If you use that technique, tell us about it.
