[quote name='evilguy69']Anyone use impulse? Can anyone affirm the quality of the service?[/QUOTE]
Impulse works pretty well. You need to install a client to download and install your game, and to get patches, but the game will run outside the client, even if you later uninstall the Impulse client. Download speed is pretty good. The client lets you backup your downloads in a format that allows you to still access and install your games without internet access (though any additional DRM on the games may require an internet connection), or even if Impulse ever closes down.
There are more rough edges than somewhere like steam -- I recall it being a bit roundabout getting my game associated with my impulse account when I purchased through the website (where I had to make an impulse account to purchase), requiring me to copy and paste serial numbers from the receipt they emailed to me into the client once I had it downloaded. The client is somewhat unintuitive also, and eats up disk space during installation (it needs about 3 times the space of the game for downloading a copy, unpacking another copy, and then installing to a third copy), but it cleans up afterward and you can configure where it puts its temporary files (if you don't have enough space on C: for all three copies -- but configure it ahead of time or it will delete everything when it runs out of space unpacking or installing and you'll have to download the full thing again).
Also the claims of Stardock being Anti-DRM are a bit exaggerated. They say they hate "DRM", but have a very narrow definition of DRM; basically they're only promising not to install long-running Services or Drivers on your machine. Their games do still require online activation when installing or if you upgrade your hardware. You also have to associate Stardock games with an Impulse account if you want to receive bugfixes, and if purchased directly from Impulse I believe they are permanently associated with your account (no transferring is possible). That said, the level of DRM they implement is pretty standard fare these days, and like they promise it all takes place in the game's executable, not in an additional driver or service that gets installed. And that's just for Stardock's games, games from other companies on Impulse can have no DRM at all (mainly true of indies).
But overall Impulse is a pretty smooth and reliable service, and they do keep a lighter touch on your games than somewhere like Steam.