I also watched this for the first time yesterday, and I really enjoyed it.
I was actually pretty happy with the amount of character development we got before the shit started to hit the fan. It was enough to get me familiar with the characters and make me care, but didn't drag things out for too long before we got to the more exciting stuff.
It really had some outstanding action/horror set pieces, like the initial attack by the trip through the hall full of facehuggers.
I was really shocked at how big of a roll Rook played, I was expecting just a quick cameo in a Marvel style post-credits scene or something along those lines. The effects for him were pretty good, there were a few kinda wonky scenes, but most of it was pretty convince. I do like how they had him malfunctioning, so it was easier to cover up the fact that it wasn't Ian Holm's voice.
The whole did a good job, with David Jonsson as Andy as one of the stand outs. He really did a great job playing what were basically two different characters, the reprogrammed Andy, who at times almost came across as Autisic or something along those lines, and the Andy with Rook's chip, was emotionless company synth.
This one was definitely the most full on horror the series has been since the original, with The Offspring being the creepiest thing we've gotten yet in the series.
It gets a 9 from me.