The original BladeLock has a 3.5" clip blade, the BladeLock 2 is shorter (a little under 3"), and a semi-wharncliffe shape.
While the lock might seem a novelty, it really works well; despite a couple years of recreational opening and closing (the lock still fascinates me), it still locks up like a bank vault door, and the solid steel frame feels solid as a rock for such a small knife.
I much prefer the original BladeLock, personally; it's slim and handy, but with a lot of blade. I don't see the original on the CRKT site anymore; I take that to mean it's discontinued. Better get one while you can!!