I'm running an Ampeg B5-R into a pair of Kustom 410H cabinets, and to my ear it sounds great. They don't over-emphasize the extreme lows, which makes my stage sound manageable in the house, but the lows are definitely there. The setup seems to be pretty heavy, but the handles are in the right locations so I can load/unload it all from my truck without help. When I really want my sound to have some real, significant soul, I use an ART mic preamp (tube with parametric EQ) and one or two ancient Bogen 200w all-tube power amps. Terribly heavy, but oh my God the TONE! In my opinion, the boutique stuff is nice but if it's loud enough to really hear that kind of fidelity in a live-performance situation then it's too loud out front (given that you're not playing through junk that just sounds, er, ungood). On the other hand, an SF2 is something I could get my brain around...
Keep in mind that if you're hearing other players through the PA, then the amp/cabinet might have nothing to do with the tone. The simplest of tube preamps feeding the PA (with no EQ) is the best option in that case, since your EQ will need to be tuned to every different room you play in, and re-tuned as people come and go and as different tunes dictate (as will the entire system). Sending an EQ'd signal to the house is not unlike tying your soundperson's hands. You might find that the same person is running the board whenever you hear a bass sound you really like. Also, some rooms just suck, and others just sound awesome, and bass is always the instrument that suffers most when they suck...
John