No spoilers. I just saw this and thought it was great. It beats Hollywood films because it portrays science in a believable way. The acting was also good and very believable. Shane Carruth did a fine job as writer, director, and actor. I give it an A+.

Film Quality: The lighting and focus weren't always perfect but neither are most big budget films. I loved that you could at least hear everything they were saying in this film unlike most big Hollywood flicks where they ruin it with orchestra music and background noise (I have no idea what Tom Cruise said at the end of Collateral and I doubt anyone else does either.) Primer does an excellent job with film quality, especially considering their small budget. I found this film very watchable.

Story and Plot Quality: The story and plot are also good, but it does get a little convoluted by the end so I was somewhat lost when I left the theater. I think I understood all but the last 15 minutes. Personally, I think the director purposely made the end hard to follow so people might go see it again. I think a simple 2 minute narrative would have filled in all the gaps. A few segues (transition scenes) also could have been a little clearer. I find that I'm still figuring things out many hours later. Perhaps it was bad editing, but more likely a directors trick to make you think and possibly see it again. I would have done a few things different with editing, which is my biggest gripe here.

Who should see it: It isn't really a movie for the family. Take an enlightened friend or perhaps a date if that person has an open mind. The first half of the movie is there just to give background and make you believe that they could build such a machine. Children and old people aren't going to like this one because it doesn't have a lot of whiz-bang type stuff in it (No eye candy for the mentally challenged or immature.) Special effects are scarce, but really aren't needed in this intellectual thriller.

Rating: I rated this movie 10/10, but I was considering it's genre also. A budget scifi with lots of intellectual intrigue. If your looking for childish, comical, Hollywood whiz-bang type crap then go rent "Back To The Future" instead. I think Primer will sort out the men from the boys here!