I have the Raven, as well as some of the other byrds. Here is a review I did of the Raven:
http://spyderco.com/forums/showthread.php?t=17497
Theres also some in-hand pics there as well.
I just tried to compare the liner lock of my Raven to the liner lock of a couple others I own. Its hard to tell but they look about the same thickness. The Ravens could be thinner, but again, its hard to tell.
Heres a very good report to read if your thinking about getting a Raven. This guy is a professional fisherman, and used his at sea. Pretty impressive IMHO.
http://spyderco.com/forums/showthread.php?t=19870&highlight=raven
Personally I like the knife. It has excellent ergonomics, and the aluminum handles give it a nice, light weight. The feathered handle looks cool also.
It also depends on intended use. If you like the blade geometry of the Raven then it should be a good choice. For the price they are ($25 INCONUS shipped), they are hard to beat.