I can see a lot of the flaws mentioned here but I was really captivated by the visuals, atmosphere, mystery and so on that i didn't notice so much while watching. I think I need a rewatch to give an honest appraisal. Mind you I liked Alien 3 so what do I know? I was not disappointed seeing it in IMAX 3D, enjoyed the ride.
A couple of thoughts:
Liz Shaw, heh, must be written by a Who fan
Sadly the cheap jack Dark Shadows TV show had better old man makeup.