I think the D600 sounds fine, just overpriced at $500. Then again the HD800 is priced at $1500 when they sound more like 1000, seems like that is common business practice these days. However at $300-350 the D600 easily beats out all the pieces of crap at Apple Store, with the possible exception of the Momentum (just talking full-size only of course).
People seem to forget that the new Denons were made to compete in the same market that Beats currently reigns supreme, so an *audiophile* sound approach most likely won't work. Basically the D600 sounds like a refined Beats, with less muddy, more quality bass and better mid/treble performance, packed in a luxurious box with BS marketing written all over it and all kinds of cool extras. The D600 is not perfect, but neither were the D5000 or the D7000, some people modded the hell out of their pairs and claimed that the stock model were borderline awful after listening to the modded version. What gives?
And last but not least, if you don't like bassy headphones, don't buy one and then complain that they are bad, period. I bought the D600 knowing exactly what to expect, so I wasn't in any shock whatsoever.