Ti West is someone who I became interested in after having seen House of the Devil. That film was extremely well done, and felt like a return to what made old school horror films so great, valuing suspense and dread, over gore and shock. I recently watched his debut feature, The Roost, and, while the film about a group of young adults on their way to a wedding getting sidetracked to a farm with some malevolent evil waiting for them was not quite up to par with his later film, or his most recent film, The Innkeepers, once it got going, it got a lot better. Its major handicap was its molasses pace in the beginning. You can see that West is trying to establish that dread and suspense, but in this film, it just ends up being a little much, and you end up looking at the clock after a while. Overall, it was a decent first feature, and if you haven't seen any of his other films*, I can vouch that House and Innkeepers are considerably better.
*I haven't seen Cabin Fever 2 or Trigger Man.