I did FOH for a heavy metal band a few nights ago and they brought their own IEM rig - a Mackie 1608 and a couple of ART 8-channel passive splitters. Each band member had their own IEM TX/RX and an iPhone clamped to their mic stand to control their mix. Worked brilliantly and I got a clean signal to my snake. I just handed them a diagram saying "what I wanted where" in my FOH snake.
I'm selling my 1 year old Mixwiz and replacing it with the 1608. I borrowed one to do a recent gig, and there's nothing it can't do over the Mixwiz and my processing rack. I won't miss dragging that stuff around and running a snake. I'm pretty sold on the Mackie but waiting to see the Behringer version before I take the plunge.