I'm totally buying Necrovision (is a steal for that price) but... what's the deal with gamersgate? Steam like? GOG like? Something else?

From the Help & FAQ section, regarding Securom DRM:

GODDAMMIT PEOPLE.
I just spent 40 bucks on GOG and 30 euros on Steam.
Then I come upon THIS,
GRRRRRRRRRR, I will probably need to seek professional help with my obsessive compulsive games buying disorder.Because there is now about 6 games I wanna buy from GG.
Anyway, I never used them - are they OK?

You download a small "Download this game" file from GG, which when executed asks you for your login, and then starts downloading setup files to a hardcoded subdirectory (like "GamersGate temporary files/1518"). It then launches the installer, you put in the serial key if it asks for one, and the game installs and runs like normal. If it finds the files it needs in the proper subdirectory (if you've previously downloaded them), it just runs the installer.
The only quirk is that the file that would be setup.exe on a retail disc is launch.dat here, and is overwritten at install time by the downloader with setup.exe. You can put the files on a read-only disc to run later, but you need to copy them while the installer is running, because of the launch.dat thing. Interestingly, if you do this, you apparently don't need an internet connection to install the game, though I'm not sure if it needs to activate something with GG at runtime. I meant to experiment with that this weekend, but I didn't get the chance - I'll see if I can install and play King's Bounty tonight with my network cable unplugged (note that some games like Mass Effect still require activation with their publisher).
So, it's a little messy, but overall not bad.

Thanks. I think I will give it a try

They're a little rough around the edges, but they're pretty decent. Take a look, buy something cheap, and see what you think. See my previous post for notes on how to properly back up your install files, though.

By the way, if someone doesn't have King's Bounty, do yourself a favor and buy it. Is one of last year best games (and my favourite one).

Just tested it for the first time, bought Cryostasis, Men of War, El Matador and Necrovision.Looks pretty good, I am downloading now two of those 4 games, all seems pretty nice and smooth.

Some good news for the curious, since I mentioned offline installation earlier: I just installed Sword of the Stars Ultimate Collection and King's Bounty (both purchased from Gamersgate) from my DVD backups, with no internet connection available (network cable unplugged). I was able to successfully install and play both games, which means that for at least these two titles, NO online authentication is required with Gamersgate except when starting a download. Sword of the Stars requested my serial key, which it accepted without complaint.
I don't know if this is the general rule at Gamersgate, or if it's just these two games. If you bought something more high-profile like the new Prince of Persia, it might be a different story. Games that require activation with the publisher, of course, still require the same manner of activation when purchased from Gamersgate.

I bought NecroVision. Hooray! My account also had a good collection of 'blue coins' (presumably from writing reviews over the past year or so), so I only had to pay US$5.

Saw this, thought about NecroVision, downloaded the demo and could not like it. It looked nice and there wasn't anything wrong except for the gameplay sucking ;)

The NecroVision demo makes a really bad first impression - the gameplay gets very fun after about the first ten minutes.

BTW Prince of Persia retail has no DRM, just like HAWX or FarCry 2 with patch 1.3.So I presume they are DRM-free on GamersGate as well.

You have to check if something has DRM in most cases the DRM is listed on the game information page. Lots of games with Starforce or Securom. The Men of War there is wrapped in Securom as opposed to the NA Aspyr version which is DRM free. Supposedly the Stalker Clear Sky is TAGES but not mentioned on the site.
A couple notes about them: I find that the person that answers support emails is very nice and is quite helpful. However it is clear that english is not his/her first language.
The site is nice but it is unclear what many things are - eg. blue coins, their use, how many received and for doing what. What member status means and what it does. It really needs forums imo.
I typically get about 20-60kbps download average from them so it's pretty damn slow. I'm in the West Coast of the USA so your miles may very.