AH FUCK I had a longass reply nearly done written out about what I thought of the game (I also just beat it yesterday), but when I backspaced at one point it fucking took my browser back and I lost it.
I'll come back later when I can be bothered to re-review it but for now I'll say it was DEFINITELY worth buying a 3DS for. I think with all seven games, it would be my third favorite in the series. After the first KH and 358/2 Days (odd choice, I know, but I'll explain later why Days is just that remarkable to me).
This is the game Birth By Sleep wanted to be.