I'm going with physical because I want DAT boxart and preorder bonuses that come with it, love the game too much. Reselling it is something that borders on heresy in my book, XD inconceivable.
Naturally I'll want all possible song & modules DLC, so I'm going to play on the JP account. My way to escape the inconveniences will be to play JUST this game on the Vita for a time, without frequent switches between JP account (PDf) and US account (all my other games).
And btw Gravity Rush is awesome, I'm having TONs of fun with it!