The Qmix is excellent as is the iPad app. We have gone to running sound from on-stage with a 16.4.2 and all five of us are either on iPads or i Phones for our own IEM mixes.
And yes, 95% of the guys on this forum play with morons. Some of the threads and the responses in almost all of the forum categories let alone this one, are extremely inexperienced and/or sorely misinformed. I don't think of that 95% mean to be idiots, it just works out that way due to reading too many blogs and listening to the wrong guys at the music stores and bars. I don't really know where some of these guys get their ideas, but some are severely twisted. But I guess if you think you'll sound "balls to the walls" plugging your HiZ mic into your bass amp, then there are just that many more places that would prefer to hear my band. Thinnin' the herd!
That said, there are also a great deal of very bright guys posting in the live threads and they do their darnedest to help those guys out in any way possible. I know the more learned of us don't always agree either. But I hope we respect the other's guy's slant on things, and try to digest a little of that into how we do things. Altho in another thread, the advice to use denture adhesive to hold a loose custom molded IEM in place was kinda wacky, the OP actually tried it and did say it worked. So I have to admit, we can all learn something from almost anybody if we open our minds.
I do agree that giving these tools (iPad, iPhone, Ipod Touch's) to guys using wedges is not a great idea. We had to lock our drummer out because he would pull his plugs and start turning up the mains because "buddies" in the crowd were telling him they couldn't hear our female lead. A more knowledgeable conclusion would have realized she sang at 1/3 level on back ground work she wasn't real confident on, and full tilt on her lead work. By the end of the night, my buddies (who are pro sound guys) came up to tell me our voices were parting hair in the back of the room.
The entire idea of getting the SL mixer was to get a great house sound and keep our hands off the channel faders and masters. The we only have ourselves to blame if our IEM mixes bit the big one. This allowed me to be a bassist and lead singer as opposed to being a bassist and lead singer and sound man. When I play, I play. When I mix, I mix. It's not a matter of can I do it, I can. It was a case of, "f*ckdat, I just came to play".
TimmyP is also very on the nose with why you shouldn't allow dimwit band mates to control their own wedges. The FOH will get blamed, the buyers will get annoyed as do the patrons. So to keep everyone safe and sound, unless you don't play with morons, don't give them access to the wedges. You can lock everyone out of the network and/or other's monitor's now. My rhythm player means real well, but until the lock out featured arrived, he would constantly grab my mix when trying to turn his guitar up in his ears.
As a heads up, Soundcraft should be rolling out a Crown IQ based app for iPad in the very near future that will go with their SiCompact series of boards. These are really better sounding consoles and easier to navigate for those not into the digital mixing world yet. They're much more $$ than the Presonus consoles, so unless you are looking for re-callable gains and flying faders (which is very nice), you can stick with the Presonus and use the rest of your lunch money on a new MTD. But for those that mix for multiple groups, I'm staying with the Presonus. I can't even bring myself to sell an analog board to anyone anymore. The feature set of a 24.4.2 trashes what a comparably priced analog board can do.
And to the OP, you bet Qmix rocks. Can't hardly believe that coming up from the days of Shure Vocal Masters and Voice of the Theaters to living in a world with a Presonus is further than I ever thought it would get.