And buying games from vendors that don't have their own outlet (or only have a crappy outlet) from Impulse makes perfect sense, as a result. Here's my confusion: if you buy a Paradox game through Impulse, there's only so much Stardock support's going to be able to do for you. Ultimately, the care and feeding of that game is in the hands of the publisher and developer of the game. So by purchasing it through Impulse you've created a multi-level support issue where sometimes you're going to have to do to Stardock and sometimes you're going to have to go to Paradox. Furthermore, some services (I don't know how much of a problem this is on Impulse but it's RAMPANT on Steam) have problems getting updates from third party publishers in reasonable amounts of time.The one place you can pretty much guarantee you'll see a game update first is through the publisher's own service.
But really, it's a multilayered support issue with Gamersgate as well. It isn't like you can email GG support for game crashes, they just handle the downloading/account/payment stuff, the same as Stardock for 3rd party games. It may be owned by Paradox (actually, didn't it sort of separate into its own a while back?), but it still has its own support service, while Stardock's is generic. Game stuff, Impulse stuff, apps stuff all goes to one support service.
Your point on patches is definitely solid, and Steam does tend to be bad with it from time to time. You can also add modding to that, see the recent oops with Oblivion on Steam.
I like Impulse well enough (I'm not crazy about clients, but it's less obnoxious than Steam's phone-home routine) and certainly hope it continues to do well. I like Gamersgate as well, and hope it doesn't go anywhere either. Healthy competition is always a good thing, and god knows Steam needs to be given a run for its money.
Ditto 
Options are always good.
Edit: Though I think at this point we're talking about two different things. I was saying that it'd be fairly natural at this point for Paradox to put the game up on Impulse since they 1) have lots of games on it already and 2) just spoke pretty highly about SD and are using GOO. You're talking about where it makes sense to buy from.
