Z1+iPad Mini?

Anyone using this as a super portable setup? I've seen that Traktor DJ runs fine on the iPad mini, but wanted to make sure that it would be reliable enough to gig with. Big gigs I would still use my MBP + controller, but this looks like a very fun way to have a portable setup.

Will the iPad mini have enough juice just to DJ? I don't plan on using it for other stuff, but would the iPad 4 be worth the extra $$$?

Refurb 16gig WIFI is the one I plan on getting btw

And since I'm going small. Is the iPod touch too small to do a serious set on? Screen wise that is.