It took me 5 hours to finish the game. The gameplay is fun. The art style and music are very well done, but I was quite disappointed by the length (and the ending wasn't rewarding, neither the boss fight nor the story). There aren't enough different enemies, fights become very repetitive.
Some core mechanics don't make sense: you have to choose 3 characters, but they never interact, and NPCs do not treat you as a group. By chance I've found one NPC (the supervisor) where dialog options differ between characters. This mechanic isn't explained anywhere. Other than that, having 3 characters is essentially a way to give you 3 lives and a slightly wider arsenal.
In practice you don't want any of them to die; the penalty is harsh and it may be better to restart the level. Resurrection costs you one very rare golden ball (I found 3 in the entire game), and the dead character's weapons often cannot be fully recovered by the others because their inventory is full. Losing a weapon is painful, since you lose all the expensive upgrades as well. You can carry only 2 weapons, and whenever you find a new weapon you must leave another behind. If you're unlucky, you'll run into an auto-save point shortly after and may not be able to change your decision. A weapon stash is missing!
The game doesn't encourage exploration. Some doors permanently close behind you, and there's no hint that this is about to happen. There are no dead ends, simply different ways to reach the level exit, but as far as I could see not different enough to warrant multiple playthroughs.
There are a number of mistranslations in the German version and some parts (hacking tutorial) were forgotten and appear in English. The voice overs have not been localized, although there are so few that they become repetitive and annoying fast.
Summary: I did have fun, but there's not enough content and the game mechanics falls short on too many points to be considered great. Recommended if you don't mind these issues.