My C2 is still one of my bigger pieces it is verstong off the spot and reads the mid lane somewhat. Hate to disagree with Beans but I think the C2 is the best PK18 pearl ever, however the silver diamond is the ball that turned me on to Lane 1 so...
Out of all the other ones I've thrown(which is 90% of the ones that have been mentioned) I think the Red Alert Night Flash was the closest. When I was throwing 16 I had one of each and prepped the covers slightly different and man oh man would I destroy THS with that two ball arsenal.
As ballcollector stated, I would stay away from the newer stuff, the cores are weaker than the older stuff and therefore don't seem to have as much pop. Plus, they moved to Mexico and we could use those jobs they took away in the good ole U.S.of A. these days.