GG's downloader lets you opt to keep temporary files (eg the installer).

GOG's big website issue is usability, they've got all the bells and whistles but are applying them without an eye towards usability. At the very least GOG's website shows some aesthetic consistency (most of the time). GG's website doesn't have this, doesn't degrade nicely with older browsers, uses really shitty looking widgets and buttons, etc. GOG's website certainly doesn't deserve any design awards but at least it's not in the class of "oh god my eyes!"
It didn't the last time I used it, but perhaps they've changed this. If they have then it is no longer DRM.

Have not bought many games on GG, but so far no issues. They have many excellent games DRM-free and at a low cost, I strongly recommend you jump in. I have the same username and avatar on GG as here, so feel free to ask me anything if you have any problems :)

LOL. See I don't see that at all when I look at GG. I love that it's brightly colored. Way more attractive when it comes to buying games.

I think that kind of design actually helps with sales too, as it makes you way more excited about buying games than the butt-ugly grey of GOG, which is incredibly depressing. Can't be good for sales IMO.

It lets you save the temp files, but I believe even with 'DRM-free' games, it still encrypts the installer. At least, the last time I installed a game, this is what it did. I still had to copy and save the unencrypted installer to a different location in order to have it in unencrypted form.

But it encrypts them, doesn't it?

In that case, yep, DRM. If you need their software, which requires an internet connection, to make use of the files they directly provide you then that's pretty much the definition of DRM.

Well, I franky love GOG's design and aesthetic, it's one of the very rare sites that impress me with it, down to the tiniest details. And I completely loathe GG's flashy and overloaded style.

So, I really, really cross my fingers for GOG not to change, on that level.

(They could tweak a few functionalities, though. Such as search functions, etc.)

Thank you very much to all of you.

It seems that experience differs depending on the age and drm of the game and of course luck. However, I should be safe with games that can be activated on Steam (handy and easy updates)

Not that I'm aware, no. I can't remember though.

Sure, the grey might not exactly be fun and peppy, but I feel like GOG.com is... well... for someone who knows nothing about web design, more sleek. GamersGate is more bouncy looking, but I think it feels clunky as hell and somewhat disorganized. Different strokes I suppose.
It's like, very mild DRM that can me very easily circumvented and done away with once you grab the installer out of the temp folder. I don't know why it's like this. They should just let you download the game installer directly.

It's great for that. I actually don't mind GG at all, and have a number of games bought through them. But as people have noted, the 'DRM-free' claims are somewhat misleading. It's easy enough to save the installer in unencrypted form, but the average Joe isn't going to know how to do that (or even that he must in order to get a DRM-free game backup). They're a pretty decent DD service though, all things considered. You shouldn't have any major issues with them if you decide to buy more than just Steam games through them.

It encrypts the setup.exe (the encrypted file is called "launch"). To decrypt it, you need an internet connection to login to your GamersGate account, to verify that you do own the game. As others already mentioned, it is possible to copy the setup.exe while it's decrypted, and save it for later use.
I'm not sure if I understood correctly, but this sounds like you're claiming that Gamersgate persuaded a developer to use SecuRom DRM. If so, then I'd be very surprised - I've never heard of GamersGate encouraging DRM, and it's somewhat contrary to statements I heard from GG members. Could you elaborate?

I just made the self-test with a small, officially DRM-free game from Gamersgate and can confirm that. As soon as the installation is over or aborted, the setup.exe is encrypted into an unknown file format with the name "launch". To restart the setup.exe, you have to run the "Download [Game Title].exe" from Gamersgate again. When I tried that after disconnecting my computer from the internet, the program automatically connected to the internet again and asked me to log into my Gamersgate account. So yes, it's definitely DRM, even for those games that are officially DRM-free, and the fact that there's a workaround doesn't change it.
I don't know any details and I'm not quite sure what to think of it myself, but from the part of the developers it sounded not necessarily as if Gamersgate was persuading them, more like they didn't have any clue at all and that SecuRom was the default option, and they didn't know they could opt out of it. Or maybe they chose to this option themselves without knowing there were alternatives. In any case they didn't put the DRM in the game, Gamersgate did that for them.

EDIT: Here's the original quote from reply I got by e-mail:

I'm a customer at GamersGate since 2007, and I've bought about 700 games there so far. I like the shop very much, it's basically the only shop other than GOG where I buy my games. In my opinion, gamersGate's pros and cons are as follows:

+ Low prices and very good sales
+ Huge catalogue (nearly 4000 games, and new ones are added almost on a daily basis)
+ Excellent loyalty system, which gets you even better discounts, and awards you "shop money" for doing things like helping others, reviewing games, or even just buying games. If you do enough of this, you can basically get a cheap game for free every few weeks.
+ Support is friendly and helpful
+ Game Tutor provides quick answers from other users if you have a problem

- The website is sometimes slow, and while it has lots of features, they aren't integrated very well. It's probably a bit confusing for newcomers.
- Support usually takes several days before addressing your problem.

+/- Sometimes they make mistakes. These can be in favor of the customer (like offering a 20€ game for 90 cents ...), or they can be annoying (like selling a game with wrong master files and taking 10 days to fix it and make it playable). From my experience with 700 games, I can say that the vast majority of games works out of box, I think I had only 5 games so far that had problems. And those were fixed by support eventually.

Since you specifically asked about the downloader: It's simple, lightweight, and gets the job done. It allows you to pause downloads and resume them later, and you can open multiple instances of the downloader if you want to download several games at once. It's biggest problem (imho) is that it sometimes triggers antivirus programs which then corrupt the download. Personally I only ha this problem for 2 games, but others experience it more often, it depends on the antivirus suite you use.