'Alien' is without a doubt the best transfer of the 4, the PQ is PERFECT and is really how a movie of this age should look on Blu-Ray. In my opinion Alien 3 is the 2nd best transfer and Resurrection is the worst. It looks not much better than a DVD which is a shame considering it has some nice visuals.
On the subject of grain, Aliens is defintely the worst culprit. A movie this dark suffers greatly from grain. I would have like to have seen it lessened if not removed.
The Extras are great and all inclusive. One star off for the poor PQ of Resurrection.
When you know the original cut, then watch the extended cut on these Blue ray disks, prepare yourself for an additional half hour of magic! It will clarify some of the things of the original theatrical version. Combine this with a beautiful transfer to Blue Ray, I am so happy with this box set. And for this price on Play.com, don't think! Buy! There is no way you are going to regret buying this item.