BrianM:
Of course a SuperFilter is an entirely different breed of animal than a conventional graphic EQ, sounding very different, but not programmable.
I've seen digital EQs ganged in PA racks, and after seeing them in BIG guitar effects rack I'm thinking they must have been MIDI to where you could roate through preset EQ 'scenes' in concert with effects changes via a MIDI controller/footboard.
Unless you're going to use lots of different preset effects/tone effects, it might be a lot of $$$ for a not much use. Plus, a lot of the better rack effects for guitar are certainly usable for bass and include EQ that you can change inside the algorithms for the other effects in the chain. TC Electronic's G*Force and G*Major for instance include EQ along with all the reverbs, choruses, compressors, etc., and the G*Major is only $399 US. I'm familiar with TC, but I'm sure lots of them are built that way. While all the effects plus EQ may not be quite the same as separate units, it would sure cut down on your MIDI headaches trying to get the different rigs to talk to themselves.
J o e y