The Aluminum Amps were released just as I was going to grab the 1350s. I purchased both and did and A/B compare on several tracks. To my ears the 1350s have cleaner MIDs, tighter/cleaner bass. I though the highs were delivered a bit cleaner for the 1350s as well, but not by much. I would also state more or less the same when comparing the 1350s to the HD25s.