If you don't mind low-budget and you enjoy sci-fi horror, then you might enjoy this.
I almost stopped watching at the beginning but decided to stick with it, and I'm glad I did, because once they get into the tunnels/pipes, it changes gears and becomes kind of unique The farther they get into the tunnels the more intense it gets, and it doesn't let up. There's no side story to cut away to, you're stuck with them, in the tight spaces till the end. I read somewhere this only cost something like $8,000 to make, which is a pittance in filmmaking terms, so I think the makers are to be commended for the final product. It won't win any Oscars, but it's not supposed to, but as a sci-fi horror film, it offers more than films costing a helluva lot more.
I've seen a lot of films, probably too many, and I don't recall ever feeling as claustrophobic as I did watching this. I read online that a Japanese critic called it THE MOST CLAUSTROPHOBIC FILM EVER... might not be too far from the truth. It certainly is relentless till the end.
I've noticed people are leaving a lot of negative remarks. I feel they're not really giving it a chance. Appreciate it for what it is. It's a comic book style action sci-fi horror chase movie, that delivers a prolonged intense chase for most of the film, and for the most part delivers a pretty unique experience. Watch it loud and with the lights out, you should have fun.