Preach it brutha!
....Honestly, I have a feel for what I know I'll like and there's very little I buy that I actually gag on when I start playing it. If I drop $50-60 on a game, without any sort of demo play, I usually like it.
I do agree, though. I miss the days when I played a demo first and THEN decided to buy the game. Not the other way around. Descent2? Score. Quake1 tech demo? Score! BF2142 "beta"? .... ehhhh. okay, score!