Wow, great review!! I knew you were going to write a review but I didn't expect it to be this long!
Well, the review is absolutely right! We had a one or was it two hours listening session comparing my dynahi with the 337, both performed exceptional and at the levels of these amps they ought to be. The main difference between the two is that the 337 is smoother, tubier (obviously), had more impact and slight wider soundstage. The dynahi imho has the edge on speed, resolution (not by much). Ultimately after 1 hr of listening, I couldn't really tell the difference that much anymore, got lost in the music and just decided to enjoy them.
Mike
BTW, we should do an UCLA meet!