I've owned both, still have the PM2.
PM2:
Pros:
Weight--light as a feather, you won't notice it in your pocket
Ergonomics--works with most hand sizes, has a choil to choke up for fine cutting
Price
Lock
Cons:
Delicate tip
I'm not a fan of CPM-S30V, though there are other options out there, but mine has been very chippy
I've hear people get some where the action isn't smooth.
Other thoughts:
This is a medium to light duty knife. Don't let the name fool you. I really like the compression lock, almost as much as the caged ball bearing lock on the Manix 2.
ZT 0560
Pros:
Elmax. Really love that stuff.
Heavy duty, if that's your thing.
Caged bearings
Flipper
Cons:
Detent/flipping action--I've handled several of these in addition to the one I owned, and they are weak, like most Hinderer's and Hinderer collaborations
Weight: It's like carrying a brick.
Flipper: Extraordinarily tall flipper, often got in the way.
Other thoughts:
If you have xl hands, the ergos are great, otherwise its much like a short sword. In the event I have a sudden urge to fell a sequoia, this would be the folder of choice.
Thoughts on both:
They are vastly different knives. There were just so many things that turned me off on the ZT, and ZT in general. I hate metal handles, and thus framelocks. With the temperature extremes we have in northern IL, metal just doesn't work for me. The flipper action on the 0560 was like a limp handshake. The S30V is really the only thing that is off putting in regards to the PM2, IMO.Both knives have a myriad of aftermarket parts available, so you can customize at will.
If Ti is your thing, I much preferred the 0801.