I've got 3 x mini's and am about to trade up my remaining full size to another mini.
How's your eyesight and tecnical prowess with small icons to press with big fingers? If you answered all good, then you should be fine with the mini.
I find my mini's run Ozrunways with no issues at all and that's the original mini that they still sell now. You can get the non cellular for about $280 and the cellular model (which you need) is around $150 more. 16 gig runs Ozrunways for me no dramas at all.
I found the biggest problem with the full size ipad is trying to mount it somewhere in the aircraft... it can be a real pain and too heavy for many of the mounts that are avaialble for it.