GamersGate is really cool, actually. I had never heard of them before looking for distribution channels, but they are pretty huge in Europe. Their stance on DRM is basically the same as Impulse -- whatever the publisher wants. So if there is DRM, it is not their fault, but the publisher. They don't have a client like Impulse, just a little downloader that distributes the setup installer, so it's a pretty simple system from that end.
They also have a customer reviews system, including literal written reviews and a star ranking system, which I think is pretty cool. My main complaint is how visually "busy" some of their site can be, but part of that is just how much content they have on there. It's a good system, and I definitely recommend them -- there's no reason to shy away for DRM purposes, unless the publisher themselves are causing it.
