How bad is it? Cheap "Alien" rip-off.
Should you see it? Not really.
There are at least 3 films by this name from the same year - this is the Christian Slater one.
The director of "Battlefield Earth" got to make another science fiction film (he actually has an Oscar for set design in some other SF film!), this time with Christian Slater. It involves an alien that can take over people's bodies and shape-shift, which cuts down on budget. They're on the moon, but the whole film is interiors - an abandoned hospital or factory, I'm guessing - which cuts down on budget. It has cheap effects, extremely cheap props (some look improvised) and mostly non-name actors, which brings costs down even more. Sadly, they didn't spend anything on writing, either. The film just starts; there's action and people and you never get any exposition to explain what's happening. And then it grinds on tediously for 80 minutes and stops.
That's my review: it starts and it stops.