Re: I Pad for digital console
Exactly what Brian said. If the unit is only a control surface, spending extra money on more storage space is a waste. Higher capacity doesn't change performance one bit.
The iPad 2 is functional today for most uses, but realize that Apple won't likely be offering many OS updates for that unit, so if new software comes out that requires a newer OS, you may end up out of luck.
The iPad mini is awesome because it can fit in a suit pocket, or jeans pocket. The size of the iPad air screen is a little nicer if you're actually mixing on the unit, but the mini isn't too bad for most uses.