hmm... Well, I heard that they improve with burn in, plus maybe the harx900's sound better or something. I'll do a review... Plus aren't the momentums 250$? That's a big price gap for comparison lol. 250$ to 30$. Look up some of the mids for those harx700's. Apparently it sounds phenomenally better.
Oh yeah, the Momentums and V-Modas are complete different level but even the HD280pro sounds better...more balanced but not cheap and dead. I let them burning for a while just in case..but that cheap and far away sound will never be for me. Never had a headphone sound like that..at least not from what I can recall. :)