Shmutt: I prefer Impulse over Steam, just for the fact that it is not geographically biased. I am not able to view/buy some of Steam games that I wanted, especially when it's one sale. A huge downer for me.
All of my digitally distributed games are from Impulse and GOG.
Even impulse offers regional restrictions, it's one of their selling points to potential partners. Including, regionally restricting who can see certain products. For Steam, if you want to see games in other regions (although you can't buy them), just add
?cc=us to the end of any store URL. And you'll force the store to the country with the matching code. Ie, US for America, UK for England, JP for Japan. You'll need to change the code back though, as the store will remember the last country code you forced.
Now, GamersGate on the otherhand, sell a few games region free, which are regionally restricted on Steam and they have the added bonus of finally dumping their client. So now you can get direct downloads from their store. Which has certainly made them a potential site to buy from as far as I am concerned. Oh, and GamersGate don't regionally restrict who can see products; but will inform you of which countries the product is sold in. Such as The Witcher being US only.