I think I said somewhere else (crap memory) that I run both of them together, the B3n in front of the G3. This means I don't have to change patches up or down very often, and sometimes I like to add a dab of reverb or a short room sound with the G3. The short reverb/delay effect really makes an envelope filter pop out big time.
Plus, the G3 has a DI, if I need one. I have a Nova Dynamics in front of the whole shebang.
The only problem I have with the B3n is that it really needs its own isolated power supply, because it is a noisy bugger otherwise.