Impulse isn't going to spam you or install spyware, and you can uninstall it after installing DC, it's not like Steam where you need to run their client to play the game. Since it's free you could even sign up with fake details if you're paranoid. I totally agree that Nitro/Paradox are being very weird about the release of DC, but if you want the patch you can get it in about 10 minutes.
tdacon: Impulse is another online store, like gamersgate or direct2drive.
tdacon: Impulse is another online store, like gamersgate or direct2drive.