Don't let the rating fool you, this is not a hidden gem, BUT it is decent no-budget film making with a fairly unique concept, and with a better script, could have ecome a cult classic.
Solid concept, okay execution, fun characters, but repetitive and ruined by an ending that blows apart continuity. This movie should have had a much different ending, it had it's problems for sure, like why do the monitors have such long cords? How convenient! But that's not really a plot hole. Also, if you know anything about time travel theories, even from the beginning, this one has huge problems, but they could have been remedied with a solid ending, instead the ending literally makes it worse and throws it's own internal logic out the window. Up until the last 10 minutes I could buy into the premise, but wow, did it just become incredibly stupid in the last 10 minutes, and not in a good way.
Still, if you are used to Japanese or Korean cinema, this is pretty typical fair acting-wise for a comedy, ultra goofy. I liked the characters, I thought that they were fun, and well-developed for an ensemble movie based on a high concept. It definitely plays the concept for laughs, but it actually gets pretty serious at some points, it has some deeper themes about destiny and predetermination, but again, it generally chucks those out the window by the end. It really does become a somewhat disappointing mess by the end, I still enjoyed it, but its sad because it could have been a hell of a lot better. I think for the most part they did a good job with a pretty tricky concept, other than the last 10 minutes. I would love to see this remade with a better script and a much different ending, this could be great, but instead, it is just barely above average.