For my FOH I have:

JBL M-PRO 415's (2)
JBL M-PRO 418's (2)
QSC RMX 2450's (2)
DBX Driverack PA

So I hope I've given enough information to get started. And speaking of getting started , I haven't even hooked this system up yet. I've been reading the manuals and such and making sure I have all the correct cables and all.
But after all that reading , I still don't know what to do when I get to the amp sensitivity screen! Some guys have said , "Oh , just ignore it and go to custom..." , well that tells me nothing. It would be nice to understand WHY that would be (the go to "custom" thing) , if that's what I should do.
I believe I have a good grasp on the basics of this piece , but this amp sesitivity thang iz woopin' my tail! Please , help a brutha out!!!!!!

I havn't set up a driverack Pa yet, but guys are probably saying go custom so you have more adjustment to the amps input sensitvitys especally if your using different size amps with different input sensitivitys and/or if the amp input sensitvity varies a little with different loads, that's the only thing I can think of.

HTH
Bill W.