I never experienced the original PS or Saturn versions, but Nightdive has been killing it with these remasters, so I felt comfortable giving this a shot. It's got some charming jank to it - your hitbox is considerably larger than other games from around this era, including other Build Engine games, e.g. Duke Nukem and Blood. That said, this was one of the earliest examples of a proper FPS / Metroidvania and it is a fun, if dated, example of it. While games like Strife included backtracking and progression across levels, Powerslave leans more into the true Metroidvania aspect of, "there is a ledge / gateway in plain sight, but you cannot access it yet because you lack the ability to (jump that high / pass those kinds of thresholds / touch that surface)," and so on.

Gameplay loop aside, the game feels fantastic. Tight controls, lovely visuals that were polished up while still maintaining their original charm (i.e. not smoothed out or giving off any sort of Vaseline-coated vibe). Kudos to Nightdive for making an old Build Engine game feel this good to play. While Ion Fury is an example of a recent game that does it well, other older examples like Blood and Nukem 3D, as much as I love them, can feel very rough around the edges. This really didn't feel that way at all, apart from some inherent jank in the original game itself from a development standpoint, like the aforementioned hitboxes.

From a price : playtime perspective, it's definitely on the shorter side. I did some extra (optional) collecting before I finished the main game, so realistically, blowing through this with no extra side collecting would probably take a casual player ~4.5 hours. Going for a full 100% / all achievements would likely add a significant amount to your total playtime, at least a few hours more if I had to guess.

tl;dr: If you're a fan of boomer shooters, and you don't mind some Metroidvania-like gameplay aspects thrown into the mix, this is a good pickup.