I'm giving this a generous 4/5, but what I really want to give it is a 3.5.
Don't get me wrong, I love Fringe. However, I'd knock a star off from 5 because seasons 4 and 5 didn't quite have the same magic as the earlier seasons. Then I'm knocking an extra half star off because of the blu-ray set itself. It's a nice box, but it's all very simple. There are some nice extras, but nothing terribly special. Season two (inexplicably) has no information on the back of its box, instead opting for a picture. Why? If you're going to print all the others with running time, cast, and synopses etc. then one would expect the same on all seasons.
Another little gripe I have is the 'previously on Fringe' recaps. There's an option on season one to turn them off. Fantastic! I've been watching through this since I got it in bit of a marathon. It's nice to not have to see a recap of the episode you just watched before (or even the other day). Why was this only included in season one? I wish I knew.
All in all, it's a great set of a great show at a very reasonable price. I would have still liked a nice little booklet with some high quality prints or something. A lot of complete boxsets have come with something extra over the years, this boxset is rather basic in comparison.
That being said, the picture quality is wonderful and the sound quality is a delight. I would definitely recommend this boxset to fans of the show, and would recommend this show to anyone who likes something vaguely reminiscent of X-Files.