This review is intended to let you know my findings on the various satgebox type mixers I have used as you are probably looking at several options at the moment so should be informative. I use several including the QU-SB. Hope you find it useful:
I had the Behringer XR18 and XR12. Good sounding unit but the apps for Android and iOS are terrible and Behringer have made NO attempt to improve them.
I looked at the QSC Touchmix but it has no remote pres. OK if you doing sound for yourself but not so much if you are doing sound for several acts where being able to recall changes saves bit of hassle during a muli-band gig.
The best app is the Master Fader by Mackie, I do not like the Touchmix app, Allen & Heath have a nice app. It is well laid out and functions well but Master Fader is by far the nicest to use.
I use an Apple Airport Express with a iPAD 4. Never had an issue. Lovely sounding mixer provided everything you plug into it is setup and eq'd correctly.
The thing to remember with any of these is that in the event of a wifi fail the mix will go on with no drop outs or fails , just you will not be able to make changes to the mix until you reboot the router etc. BUT if you program the footswitch on the QU to mute fx for 'between songs' announcing you are good to go in that regard.
One good thing about the Behringer XR series is it will allow you to control it with a hardwired PC/MAC, phone and midi hardware all at the same time (you will have to understand and know how to program midi cc's etc) giving you 3 simultaneous control options.
QU-SB will allow you to record BOTH to Qu-Drive AND MAC at the same time giving you a backup, I do not think the others allow for this even the DL32R. A big thing for my choice to purchase.
With any of them, run your router at 5 GHz, be sure your tablet is spec'd for 5 Ghz wifi pickup.
The QU-SB has no HiZ inputs you will need DI boxes, the behringer has 2 from memory.
I have used the QU-Sb for work doing sound for drama groups, choirs and bands and it never let me down. The Behringer internal wifi - just don't use it, the XR series sounds nice though.
So, for the money and the sound quality, good app, space saving on a small stage etc the QU-SB is the pick of them for me. If I could make my dream system it would be the functionality of the SB with the Mackie App and the ability to run hardwired to a MAC giving additional control.
Had Mackie priced the controller for the DL32R cheaper I would probably have gone for it (32 ins), then again it has cooling fans (not ideal if used as i/o with your DAW) and one less fx engine and will not allow recording to drive and PC at same time.
If you do a 'one man show' check out the Soundcraft Ui12 as it has amp sims which are not bad and means you have one less thing to carry to gig etc. It also has a music player you can run backing tracks from for less than ?300!