I bought a used pair of these portable (battery powered) noise-cancelling headphones recently, to use on the BART, and I really liked them. They deliver performance comparable to the best Bose or Sony stuff, at a significantly lower price point (admittedly still not cheap, but, well, $200 is significantly less than the $300-350 I was seeing for the comparable Sony and Bose models; and I got the used pair for somewhat less than that). Unfortunately, after a couple months of frequent use, something in the electronics died, and they stopped working. I was really bummed because they were not under warranty (and even if they were, I would've needed the original receipt from the guy I got them from). But I got in touch with tech support, and shipped the 'phones in to their service center.
They sent me back a brand new pair, along with a note saying that they concluded there was a manufacturing flaw in the ones I sent in, and they were replacing them free of charge, even though they had survived past the warranty period. They even paid the return shipping.
I figure when a company exceeds my expectations by that much, they deserve some recognition.