I thought this would be a good place to ask since GOG users are not fans of DRM. I'm looking to take advantage of the preorder deals for this game to get the copy of Red Faction 1 and 2 for free included with preorder. I first saw this deal on Impulse in July and then saw it was also running now on Steam, Direct2Drive and GamersGate. I never got around to ordering and it releases on Tuesday, so I figure I better get my butt in gear. I don't have extensive experiences with all these services, just very ittle with Steam. Due to this, I can't really compare the pros and cons of these various sites.
I generally prefer physical copies and I'm no fan of DRM, so I'd appreciate any input on which service would be my best bet for long term access to this game. I hang onto my games as I like to revisit them in later years, hence why I'm here buying older games I missed or ones I'd rather not spend hours trying to figure out what box the discs got packed in. I'm a US resident, so currency conversion isn't a problem for me as it seems to be with many using these services. The only price difference for me is I see it was 4 cents less on GamersGate. Thanks for your feedback.

Get it on Gamersgate or Impulse.
Impulse will update it as long as you have signed up for their service, BUT it isn't necessary to be signed into impulse to run the game.
but Gamersgate is not bad either.

Gamersgate, because no signing in at all after downloading, being completely identical to the retail version. Impulse is nice if you still want a neat frontend, or Steam if you're drunk. D2D if you live in like, the three places that they claim to sell to (but I think it's worldwide for Red Faction).
D2D's Red Faction and Red Faction 2 preorder is DRM free.

Impulse or Gamersgate are your best choices.

this isn't necessarily true, their installer is password protected and will phone home to their servers, YOU DO have to be online to install those games.

I chose Impulse, because of the mere fact that it was by far the cheapest choice for me.

Personally, I would have rather had this game on Steam (as I like all my FPS games to be in one place), but seeing that Valve have decided I need to wait until October 29th to be able to buy this game when all other services are selling it on the 15th/18th of this month, Steam is pretty much ruled out.
Given the size of the game and the average download speeds I get from GamersGate, it would take a good 24 hours to download the game (if the downloader doesn't crap out and auto pause while I'm sleeping) vs the 7 or so hours it would take over Steam. So GamersGate isn't really viable for such a large game either.
Impulse too, are ruled out due to their current pricing policy. I simply refuse to buy such an expensive game while not actually knowing the price they are *really* charging me. While they may be charging me $39.99 USD, for all I know now they could be marking it up to a far higher price. That's a risk I am not taking.
So that just leaves D2D who for once are selling the game worldwide (with the exception of Germany). But their download speeds are comparable to that of GamersGate and their support even worse by all accounts.
So unless Volition/THQ can finally beat some sense into Valve and stop them from needlessly discriminating against my location, this is one game I will simply pass on.
As for the OP, would advise you to use a service that provides a decent download speed for you, GamersGate is in Europe, so the speeds you get from them may not be as good as those from any of the other services.

Converting the prices back to USD isn't hard.

Why is there even a debate about this?!!??!?!?!
Let it pass for 4-5 years and it should be on GOG!!

But isn't the difference between all of these services vary by a few cents here and a few cents there? It may be an annoyance, but it's pretty small.

Not anymore. As Impulse have started sneaking regional pricing into their prices which makes it a little harder to spot (Demigod for example has now become regionally priced at a point higher than $39.99). And I'm not about to waste time finding prices on other sites, converting those to JPY/converting Impulses prices to USD just to make a sale on Impulse. I'll take my business elsewhere and save myself that unnecessary hassle.
Point is, I'm only mildly interested in this game (having not played either of the first) and these current issues with Steam/Impulse do nothing to make me any more interested in purchasing. Especially given the lack of a PC demo. So I'm pretty much going to take the far easier route and not bother with this game until the eventual weekend sales.

I'm pretty sure Impulse is always the way to go if you are worried about DRM.
I got the game on Steam, since I make all my digital purchases there when possible, due to the community features and such.
It needs mentioning that the game will include Games for Windows Live! no matter where you get it from, which some say is another form of DRM. Also, Voilition's last game required Steam, even if you bought it on Direct2Drive and other sites, or retail... I don't think this one is doing that, but I don't think they have said 100% it is not either.

The retail version uses Stardock's Impulse Reactor for online activation. Impulse Reactor's feature set is SecuROM-like including things like limited activations and so forth, but I don't know what feature set Guerilla uses. Protecting a game with Impulse Reactor isn't quite the same thing as protecting it with Steam so it could be that non-retail releases won't use it.

Bollocks to that. They're all overpriced. Wait a month or two and grab a retail version for about half of that. By then we should know what DRM it has too.