TC, do the starter edition. I guarantee that if you're getting a bit tired of the game by the end of that (which I think I was equivalently far when my enthusiasm died down) then you should definitely avoid it at all costs. It really doesn't get any better, at least not on the first playthrough. Act 1's the best looking part of the game. Act 2 is terrible, act 3 is close second, and act 4 is too short to matter. Anyway, that's my piece. I'm not a fan of the game, but do give the starter edition a really serious look. Again, if your enthusiasm's dying down by the end of it, you're probably not going to like anything else the game has to offer.
Also, Blizzard games don't get price drops. Whoever suggested "Wait for a price drop" has never looked at a Blizzard game before. --- If you think my name is silly, you should call me either Rob or LaughingThesaurus. No need for being strictly formal on a message board, right?