I listen mostly to J-pop and Vocaloid (just think of it as electronica) and the M-100 fit those quit nicely. I don't think I can really add much to the discussion sound wise for the M-100, so the only one thing left for you is to order one and take advantage of the 60 days return policy and listen for yourself.
I know what J-pop is (in fact I first discovered V-Moda when I saw someone wear a pair of white LP's in my hotel during my time at Otakon!) I have to say I was impressed with the sound then and those were the regular LP's. I kept waiting until the Mythical M-100's would finally come out before I would decide to get them. Just now blowing most of my paycheck into this (I only get paid on the 15th and 30th of each month) needs to be better justified in my mind before I can finally buy these right away.
Lucky for me the Matte Black is the type I am looking for, it just looks nicer with my look. Have the M-100's been scaled to work with mainly iDevices or does it work equally well on most PMP's? I still use aWarning: Spoiler! (Click to show)
Also as for the custom shields option, this image will translate well when printed onto the custom plates right? Do I need to modify it since it will need to be white on black plates or will the printing be able to do this automatically?