I prefer GOG because of the DRM-free option, and I like what they stand for. But, you’re right, there are a few cases where you’d want the Steam version instead. I’d say ask the community around the game and see what they think. There are no cases I’m aware of where not having the Steam version would be a problem, but I don’t play games like that.

GOG does a few things better than Steam, though. They fix stuff. Steam just pushes what the publisher gives them. Two cases, same franchise… same shitty developer. Fallout 3 shipped with DRM called GfWL (Games for Windows Live), basically Xbox Live for Windows. GfWL failed, but Bethesda didn’t take it out of Fallout 3, meaning to play Fallout 3 on PC, even if you bought it legally, you had to crack the DRM, which is illegal in the US. No one got in trouble for doing so, but that’s what you had to do. GOG just took the DRM out. Problem solved. Something like a decade after Bethesda created the problem by not taking it out themselves, they did just that — VERY recently, and thus, it became “legal” to play Fallout 3 on PC again. Second case, Fallout 4. Same developer/publisher. Different case. They put out a patch about a year, year and a half ago, and it broke the random NPC generator. There was a cursed combination of variables that could make up an NPC, that if it generated that set of variables, you could never get close to that NPC, or your game would crash. Modders quickly found the problem and told Bethesda how to fix it. They refused. More to the point, they ignored the issue. I don’t think GOG carried that update for months. They refused it. You could only get the older, last working version for a while. I think they eventually allowed it, but with a note on it saying it was broken with no fix in the works. Couple weeks ago, they said they fixed it… after like 16 months. But introduced more problems. (Disclaimer of bias: I own Fallout 3 and Fallout 4 and all the official DLC on Xbox, Steam, and GOG. I used to be a big fan of Bethesda, but after Starfield… I am discovering way too late that it’s not a tenth the game the Mass Effect trilogy was. Better late than never, I suppose?)