Just rent Dead Space. It's a lot of fun but it hasn't much replay value.
I guess it depends on how you judge a game purchase-worthy. I've always bought on quality, never length.
Oh, me too, but I've got to be frugal, and if I'm going to only play the game once -- even if I treasure the memory! -- I can't justify $60.
That said, I loved Dead Space and I'm looking forward to any possible sequel. I played it with a large audience and it was a
blast -- some of the deaths got a ton of cheers, in particular. And I had to play the final boss battle upside down in order to complete it, which earned standing applause. It was fun!
EDIT:
can't justify 60, not
can