luces, I’d say 4 iPads with the mix pad app would be ideal for your setup – everyone controls their own feed to the ears, and you can get a mount to attach the iPad to a stand so it’s not intrusive or hard to position (plus – no cables!). Of course the beauty of having a system like this for your band is that you’ll have absolute recall-ability and the capability of saving programs to suit your regular venues – saves a huge amount of time on setup!
I haven’t checked if its on that video page, but there was a great video also of an engineer with a Motown band saying some of their corporate work comes from the fact that they have such a small footprint (no stage monitors, no FOH console (using a wireless laptop), and a single rack holding their mix rack & ears transmitters) – very clean and easy for designers to fit into an event! You might even see some more work from having this type of rig 
iDR32 mixrack
MixRack for iPad & Tweak for iPhone apps
Asus N61 Laptop (x2 wireless)
Sennheiser IEM (for PFL)
Dante card (soon!)
