If GOG offered torrents, I not only wouldn't use it, but couldn't. I happen to have one of those ISPs that actively throttles or outright blocks BitTorrent traffic. At best, all I could do is leech downloads without providing any upload. Might as well just use the direct download at that point.

If it's optional, I say yes.

I like the way it is right now. GOG did a excellent work, and I vote for not changing the download method.