Cool! I've never really used software instruments live, until I noticed I wanted to use sounds that I didn't have, and that I would have to buy an expensive workstation or an ugly yamaha keyboard or something. So now I've started to use my iPad as a sample library, with Sample Tank, Arturia iMini and Manetron. I must say that although I've got some great gear, it does sound tempting to just have to move 1 midi keyboard, plug it into MainStage and be able to play just about everything. I just love making sounds live, not playing preset after preset. Adjusting sounds live makes it so much more fun to do. Every gig sounds different, because you feel different every night. Of course the big advantage of presetting everything is that certainty that everything sounds the way you want it to.
Well, hell, here's my stage setup right now:
In front of me a Korg R3 (mainly for synth leads, and a couple of cool polysynths)
a Clavia NordStage (still airforce 1, all my pianos, rhodes', wurlitzers, hammonds and other organs come from that thing, I've got it since 2008 I believe, still working great, not a single fault)
Behind me a Korg MS20-mini (mainly a gizmo, I use it effectively just a couple of times each show, but it looks cool, and I do a lot of cool effects with it)
And a midi keyboard, built in a mellotron-lookalike-wooden thing that I bought off off the dutch ebay last year. The midi keyboard runs through an iPad, via a Line 6 Midi Mobilizer II, but that thing's dreadfull, I'm buying a iRig midi-thing soon. The iPad, as I said, mainly runs Sample Tank, for horns, strings, mellotrons, electronic drums etc.
In my fake mellotron there's a ART MX822, all my keyboards go to that thing, which is a 8 stereo channel mixer and DI box. It just has volume and panning, so no excessive buttons like on a mixer, and just two outputs so the front of house don't go crazy.
On the floor I've got a couple of sustain pedals, a controller pedal, and one specifically for the leslie speed on my NordStage.
Lastly I've got a monitor that I carry around to each show. There's a monitor output on my DI mixer, so that I can adjust my monitor volume every second of the show, without disturbing the sound engineer. It's a Mackie SRM 450, great thing.