Hi, I just have a question about how important frequency response is in a pair of headphones. There's two sets of headphones I'm considering - the Grado SR 80's (£90) and the Sennheiser HD600 Avantgarde (£150). The frequency response of the Sennheisers seems to be way better at 12-39,000 Hz, whereas the Grado are 20-20,000 Hz. I would like to choose the Grado since they're much lighter and supra-aura, which I prefer, but would the Sennheisers sound comfortably better? The reason I ask about frequency response is that I'm buying them to connect to a PC sound card (Audigy 2 ZS) for gaming and mp3s, and I'm thinking the samples used in games and the relatively low quality of mp3s might not need a particularly wide frequency response. Also could someone maybe compare Grado and Sennheiser (and any other brand) in general. What Hi-Fi seem to give just about every set 5 stars, which isn't very helpful in distinguishing them. Cheers, Simon.