I know there's been a bit said about how bad this switch is, I just want to add to that. I just pulled it out of my 4343B's and totally bypassed it. I'm running in biamp mode and there's quite an improvement without that damn switch. Greater clarity in the highs and more slam in the bass. It's pretty indistinguishable from the improvement i saw when going active 4 way. In fact I now think the improvements I saw between active 4 way and biamp were mainly due to not going thru that switch when Active 4 waying
Not sure if this thing was only used in the 4343's, but definitely recommend bypassing it if you haven't already. I won't go into it, but the thing is so poorly designed.
On another note, I also just side mounted them, actually rotating the baffle and everything. It's pretty cool.