So ultimately I ended up returning these and keeping the HD25-1 II's. The decision basically came down to portability and price; it's simply near impossible for any headphones to beat the HD25's on portability factors IMO... it just combines those size, isolation, durability factors so well in one package. Yes, the Momentums do well in those departments too, but you're really never going to treat the Momentums roughly like most people would do with HD25's without worry (which really makes things incredibly convenient and stress free)... because it's just too damn nice! The second factor is the price... as I mentioned earlier, at $400 IMO these were too much for the sound quality... and it didn't help that I'm currently looking to make improvements in my stat rig and needed that extra money.
However, I may very well re-acquire these headphones in the future (hopefully in $300 range next time) to use as a transportable home/work use headphone. Provided that one can get these headphones at ~$300 range, and have small ears, I would definitely recommend these headphones for people who want fatigue free, smooth sound signature.
Edited by K_19 - 11/14/12 at 6:28pm