Some measurements for you. The PM2 is 0.145", the Seb as you know, is 0.125", except that the new 25's are 0.140" like the Zaans.
The handle thickness is .450" PM2, 0.455" Sebbie, and 0.470" in the Zaan. Weighing 3.75 oz when in G10 format, the PM2, with 3.3" blade, carries like a dream. The PM2's are commonly available in G10, the nicer ones in carbon-fiber or titanium. The Sebbie is 4.7 oz and 3 oz in large and small editions.
When it comes to steels, the PM2 is (or has been) available in MANY of the supersteels that would make S30v or S35v blush. The cheapest PM2, at about $100, comes standard with S30v. Blade edge retention with PM2 steel such as S90V, M390, CTS-20CP will surpass CRK's easily. The ease of lock/unlock in the compression lock of the PM2 is outstanding.
Yes, with all of that, I've traded or sold most of my PM2's in order to "step up" to CRK.
The cheapest PM2, with S30v, is about $100. The more expensive PM2's, looking at the original pricing, only went to about $200, even those with the supersteels. Those same knives today, with S90v, limited to 600 knives total, probably will go for $400 and up, if you can find them. The lesser blade-steels that still far surpass S30v go commonly for $190-$250 or so in new condition.
Yes, they are both excellent folders.
CRK stands for excellence and tradition. IMO, however, Spyderco PM2 is a sleeping giant.
Here is a pic showing the blade thickness of both.
