While I love the cue-ball look of that lock ball, I'm not sure how well grabbing a ball to unlock the blade will work in practice. It would probably be more functional if they did something similar to the manix lock and put something grippy in front of the ball. But then they would have covered up the most visually interesting thing about the knife.
Seems like a reasonable price on a g10/s30v seki Spyderco, which of course means it's discontinued and this is a clearance deal. Get one while you can if you want it, it probably won't be back.