Let's get this out of the way first; the original Jacob's Ladder is a great and unique film that by no means needs an updated version. If you want to watch a great version of it, just go watch the original.
Story: While it is a remake, it is not a shot for shot reiteration. Several key story elements have been changed up, but many of the scenes reappear in a different context. The problem with this is that some of them feel shoved in to pay fan service to the original. The changes to the story and characters are at times major, and it feels like they are trying to tell a similar story just with vastly different parameters and it doesn't quite fit right.
Acting: The three main actors do a very serviceable job in their respected roles, however Michael Ealy really wasn't able to fully capture the same insane paranoia that Tim Robbins brought.
Production: The cinematography, while not bad, was lacking creativity and polish. The sound design was solid throughout. The effects on the other hand were cheesy and repetitious. They drastically overused the sped up head and camera shaking effect, while the cgi would have looked like it was 10 years old, 10 years ago. Seriously, half-assed practical effects would have looked much better than this shoddy cgi.
Entertainment: Well, there was little. It honestly felt like one of the most generic and predictable films that I have seen in a long time. I understand that it's difficult to make a remake unique, but this iteration has no heart, enjoyment, or identity to it at all and it just falls flat.
Overall: It's not the worst movie that you could watch, but there's really no reason to watch it. It's bland, mediocre, and the only thing scary about it are the bad special effects. Like I said before, if you want to watch a great version of it, just go watch the original. A generous 4/10