I sort of question how much of this is just personal preference (probably a great deal) and how much is variability within and between lines. I would imagine that no two pairs of 225s sounds identical (nor 325s or any other). So, given that much of what is being discussed here is nuance - it is entirely conceivable that were WhiteCrow and BarleyGuy to trade cans they may in fact find agreement. The within-line variability may in fact be almost as great as between-line variability. Unfortunately (correct me if I'm wrong, gentlemen), everyone here responds from a sample size of one.
I'm coming to the Grado line from closed back Sonys. I figured both the 225 and 325 will sound spectacular compared to that, so I went for the 225. We'll see once I get them.