Dan:

I have to agree with Dar on this one. A pump on a 46FX is like putting a Balenciaga dress on Miss Piggy. She looks no better, just costs more money that way.

Properly set up no common glow engine is going to run any better on a normal sport plane with a pump or pressure (Cline/Iron Bay) system.

There are special cases, a scale plane that just will not allow a large enough tank right behind the engine for example. Or a sport twin with small nacelles, using a single tank in the fuselage.

Even flying 3D with the nose straight up can be made to work well without anything more than muffler pressure.

All this being said, if you want a pump to play with, get one and enjoy it.

Bill.