Hmm, it seems this film suffers more than it gains from being associated with Wes Craven (though I've never rated him that highly, personally - so I approached They with a relatively open mind).
And it's ok. It has some good ideas, and a lot that is rather average. It's like an episode of the Twilight Zone, or in more modern terms Heroes, in that respect. Some scenes are well done, the swimming pool sequence is an homage to the scene in Cat People (the black and white original) and it rattles along at a reasonable pace with a few twists and sudden scares. At under 85 minutes They doesn't outstay its welcome either.
Wes Craven was probably happy to lend his name to it on account of these factors, and because he has always it seems been interested in exploring the collision between reality and unreality in his own films (albeit in a popular psychology sort of way, for my money). That aspect of the film works well enough, though the alternate ending makes it clear that the film makers were a little unsure themselves about where they were going with it.
It's no classic, but an entertaining enough yarn, with a few effective set pieces. I think it would probably be a good introduction to more thoughtful western horror for young teenagers, and was watching it thinking that my son (currently nine) would enjoy it in a few years, before he's ready for more grown-up and disturbing fare.
Oh, Laura Regan is so similar-lookin to Mia Farrow in Rosemary's Baby that it's probably the spookiest thing about the film!