Pros: Good audio quality, excellent sound-stage, decent price,
Cons: Lacking on the lower end spectrum of the frequency response.
Bought these for pc gaming and listening to music from my pc as well as my first foray into more expensive headphones(these aren't expensive by head-fi standard I'm sure).
Before these I've been using KSC-75 for home use and a pair of Soundmagic PL-50 (now broken).
It's extremely good sound-stage definitely helps with first person shooter for positioning especially when used for games with a decent audio engine like Bad Company 2, countless of times you'll be able to tell where the enemies are just by listening to audio cues alone. Something that wasn't possible with the PL-50 or the Koss.
Music; my source is a Xonar DG with Foobar 2k via WASAPI in exclusive mode.
When listening to BGM/OST tracks such as the "The World's Enemy (from FFVII "One-Winged Angel")" rearranged by Kazuhiko Toyama for FFVII Crisis Core, I can clearly hear the separate instruments clearly and there's obvious separation. Unfortunately, there is a need to bump up the 30Hz and 60Hz EQ by +10dB and +5dB to get the best from this track as the heavy percussion drums are part of the best part of the track.
Other genre that I enjoy such as rock, alternative are also more enjoyable when using this pair of headphones compared to the really in your face feeling of the KSC-75 although compared to some of the earlier Plantronics gaming headphones, the Koss is no slouch either.
As I mentioned earlier, these headphones seems to have very good soundstage; so if you are a big fan or orchestra music without having the hassle of paying expensive tickets and getting to the venue (but those are still worth going!). These are VERY enjoyable for orchestra arrangements with multiple instruments coming at you and you can almost feel the space.
This pretty much sums up my first review for my head-fi.
(I actually lurked head-fi for many years but managed to keep my wallet sane but I've signed up to response to a trade thread this time)