Im not a huge fan of zt's much anymore. They are art knives imho. 9 out of 10 times I'll pick a blade geometry suited to doing work over any zt. Too thick behind the edge. Plus the lock geometry issues that they have. They are more for the gun market than the knife market if you ask me.
But the quality for the price is hard to beat and they usually always have good action.
My favorite is the 0562cf. I wish I had the funds to do a regrind and make it a thinner slicer. And it needs a detent ramp. Think those are the only issues I have with it. 2nd would be 0804cf. It's not perfect either.
I have alot of zt's, don't think I can count them all. Maybe 8 or 9?.