I haven't read the thread (but I read the title!), but the one thing I don't like about GOG is that, in some cases, their gaming updates lag behind Steam's by a decent amount, or sometimes don't seem to get updated at all. That's frustrating. I really don't know how widespread or frequent that actually is, but just the fact that it's a thing turns me off to GOG. I would otherwise love to embrace them as I like their business model much more. Priority #1 for me is the everyday user experience though.