I buy the game, but only if I decide it's worth the risk.
I eliminate the risk completely by playing the game thoroughly before buying it.
I'm not going to waste a week of time trying to download a 2-6 gig game off of the internet which may or may not even work, and may even harm my computer.
If it takes you a week to download a game, then I can understand your reluctance. For most people, it is just a matter of hours, during which they can do other things while downloading in the background.
I don't like RTS's much, but I bought Company of Heroes and loved it, and I'm playing through it again because I played the Homeworld series and Dawn of War, and knew Relic could deliver a game I could enjoy regardless of genre.
While I'd love to have faith in every developer, reality does not allow me to. I loved Gothic 1 and 2 (in spite of generally mediocre reviews of both) and bought them. Gothic 3, however, was a complete mess. Luckily, I pirated it and discovered this for myself.
As I said before, the best research you can do is simply play the full, final game for yourself.
This comment was edited on Mar 10, 06:48.