If it's anything like our Vue, the premium seats are the ones in the middle section, about halfway towards the screen. No other difference, though. As you say, that's no good when the seating's either GA or not checked -- in that case there's no point in paying the higher price.

(Haven't seen IM or IM2, so no commentary there! I can -- and do -- agree that RDJ is great fun to watch lately, though.)