I own both.
PM2 if you'll just be doing light-medium cutting chores. The ergos are fantastic, and it's very light. If you don't like the blade to handle ratio then hop over to the ZT. S30V is a great steel and ffg makes it an excellent excellent slicer. compression lock is unique and fun. PM2 is also a great option if you like the 4 way position pocket clip.
The ZT is more beefy and can take more punishment. Elmax is fantastic. My Elmax didn't have any of the supposed problems faced by some of the people on the internet. 0801 can slice well, but not as well as PM2 because of the thickness of the stock and the grinds. If you like flippers then I would highly recommend 0801. It's flipper action is up to par with my Shirogorov. It's fairly snappy. Ergos on the ZT is very very nice and the lack of jimping just eliminates the hot spot on the spine of the knife. It fits very very well in my hands. The 0801 is definitely more fun than PM2 and it'll be no slouch in performance either. For a titanium flipper,ball bearings, and lock bar stabilizer/overtravel + steel insert under $200 is excellent for the money. It is heavier because of the two slabs of titanium, but I don't mind it. I love Spydercos to death, but 1:1 blade to handle ratio just looks better. You do get more cutting edge with the ZT.
Both knives are must haves... but I honestly prefer the 0801 over the PM2. I'm just a big flipper lover.