Look for one with high CFM, but with total variable speed.This way you are not restricted to the factory presets low/med/high, and can dial-in just the right amount of venting for the situation.

Actually, it's more complex than that. This is a topic that has been discussed ad nauseum on this Forum. The simplest answer is that a remote blower is always superior to an internal blower. If you have the ability to do one, it will far outperform any internal blower from noise standpoint. There are many other subtleties, including baffle design, ductwork configuration, use of a remote silencer, etc.

Far and away the best bet is to sit down with a glass or two of wine and search this Forum for ventilation threads.

Here's one place to start:

Vent hoods and noise, the real scoop