I think this is the best price on these so far.
I bought the headphones recently (before the deal, sadly, but I was in urgent need of new cans when my last pair suddenly died), and they are great, especially for anyone who likes deep rumbling bass, and the sweet Sennheiser tones through the rest of the frequency range.
They're a little more scooped than the likes of Sony and Bose in the low mids, which seems to give the impression of openness, that you're listening to a good set of speakers rather than a pair of headphones. Clarity is fantastic, and the powerful low frequencies are on a league of their own compared to anything else I've heard so far.
I haven't encountered any glitches, but I've only had them for two days so far!
ANC is fantastic, transparency mode works well too.
Outstanding sound, for me it's better than my xm4, xm5, bose QC and 700s. Noise cancelling is not as good as those though but still great. Top tear comfort.