I had a B3 and it's nice, but I found that I really only need a couple sounds, so it was overkill. Plus, all of the options caused tweaker-itis.
I switched over to an Ampeg SCR-DI and am really liking it. Very simple to get good sounds out of. Also, it sounds great with headphones and the Aux in makes it an excellent and fun practice tool.
Ever since dumping off my GT-6B I have avoided MFX boards. If I was going to go that route I would lean towards doing it computer or ipad bassed with amplitude. In my other thread I talked about my home practice rig I use guitarix (linux geek here) and a presonus audiobox for rehearsing at home with headphones. It works well enough for practice but trying that out at a rehearsal it took just half a song for me to ditch that out of the chain. Too much of a playing distraction worrying about a computer while playing. At least for now.
Ken