Is it practical to buy an in development game on GOG? Or is it like a "support pack" and you'll need to buy the finished version separately once it comes out?

I've wanted to buy a couple, but I don't want to risk wasting money.

You'd be well-advised to hold off buying newly-released in-dev games till there's sufficient feedback to get a reading on it, and to see how well the devs are supporting their product. Let somebody else be the guinea pig. ((;--))

I don't use Galaxy, so I'll just need to download the patch or installer for the final version, right?

Main advantage, besides supporting the game's development, is that Early Access games are often offered at a cheaper price due to a lack of content and when the full game releases, it usually get more expensive.

Yes. Think of it as a typical GOG update.

Thanks Grargar, you've been a great help! That's pretty cool. I'll probably get it in-dev then. The creator has been updating it regularly so I'm sure it'll get finished.

That is one thing that GOG seems to have done fairly well at (from my pedestrian perspective) -- picking in-dev games to release that actually wind up coming out of GID. Though I'm sure there's a number that have officially been fully released, but which were still not really finished, compared to what the devs and/or players had hoped. And, of course, there are those like Project Zomboid, where the expectation from early on was that they'd take years and years to reach 1.0.

You are welcome.

I tend not to buy unfinished games because too many of them stay unfinished. I'll buy it when the Dev is finished making it. I don't understand the In Dev or Early access games. "Come buy our game and get a chance to be unpaid beta testers for it!"

It all depends I guess, some of these games have more content and are in better shape than so called finished products. On the other hand, nowadays games often get patches and updates for months or even years after release so where's the difference really? One point zero doesn't mean a jack anymore.

Nine years in Early Access/In-dev has to be a record of some kind? Closely followed by Exanima with seven years. At least it looks like they are both still worked on and haven't been given up. The episodic Kentucky Route Zero also was finished after about 7 years, IIRC (without being labeled as EA/In-dev), and I guess good things come to those who wait, but by the time it was finished, I realized I wasn't even that interested in playing it anymore, it was more of a 2013 thing to me. That's something you need to keep in mind, too, when buying EA/In-dev games - it's not just about whether they will actually be completed, there's also no telling how long it will take to get there and whether you will still be the same person with the same interests by then. (Assuming you're someone who will want to wait for the final version; if you someone who enjoys to play games while they are still being worked on, that's different.)

7daystodie has been in Early access 10 years this December, the same with Star Citizen.

I've heard it's actually been in public beta/alpha/(maybe pre-alpha?) since before Steam even started its "Early Access" program -- something like 11 or 12 years. EDIT: Yep, looked it up -- it was released "as a paid pre-alpha tech demo" in April 2011, apparently via their own website. It went up on Steam about two and a half years later.