Extremely well done
I've always written off the Amityville legend as a hoax, and after seeing this, still do (more than ever), but I was pleasantly surprised at the quality of the flick's craftsmanship. It looks great, holds your attention, and is very cinematic.
About 30 minutes into it I realized the filmmakers aren't necessarily trying to convince you of the whole Amityville story, but giving you a look at this weird, angry, and uneasy dude who claims to believe he experienced it all. I thought the film was highly effective in that regard as well.