I believe I got these in around March 2011, and now is December 2011; they have gone through heavy use. The sound just went out on the left side today, but until now, the Logitech H530 headset has been a good purchase.
The on-ear volume control is great; when I first got these, I didn't think that I would have much use for the on-ear controls, but I use them all the time now.
As for the different sound settings on the on-ear controls, there are three: music, video chatting, and gaming. I know absolutely nothing about gaming, so I don't understand why you would need a sound setting for gaming, but here are the differences: the chat setting is quite normal, perhaps a bit better than what you would find on your computer's built-in speakers, and it's not terrible for music; the music setting boosts the bass a bit; and the gaming setting seems to have a bit more echo than the other settings.
The sound quality is quite crisp for a headset of this price. I've found that if I'm multi-tasking on my computer (e.g. listening to music on iTunes whilst recording something from my webcam), there are little blips in the sound, but apart from those times, the sound is great. I would recommend that you switch the sound setting depending on what you're listening to, but sometimes I can't tell the difference between the music setting and the chat setting, so it really depends on the quality of whatever music you have, or the quality of what you're listening to.
Ergonomically, I think it's quite good. It's a bit loose on my head, so sometimes if you tug on the wire a bit too hard, it can fall off easily, but I don't have a particularly large head. I also wear glasses and can put this headset on for relatively long periods of time without getting uncomfortable (1-2 hours, much better than a lot of other headsets). It also has quite a nice, clean look to it.
Overall, the strong points of this headset make up for its drawbacks, except for the fact that the sound went out in one ear after less than a year. I will probably continue to use them for a bit, anyway, just because they still work and I don't want to spend the money on another headset right now. But the H530 is, in my opinion, the best valued headset you can get at this attractive price point