Okay the handles, blade, and lock are usable. How so? How is it different than their other knives? Other Spyderco's have G-10 handle, similarly shaped blades, and ambidextrous clip positions... The only thing I can think of is the Compression Lock. Other than the geometry of the blade and handle, is the only other difference/feature the Compression Lock? Like in other threads I've seen, people would simple give generic responses saying that the Paramilitary's <insert here> is "just" better without explaining how so...
People are giving generic responses partly because people simply like the knife after using largely to personal preferences, and partly because the topic has been discussed extensively in the Spyderco section and this topic is in a different section which the bulk of PM2 users may not see. Putting it in words is more difficult because the knife is vastly different from most three-inch folders. There are few knives with this style blade shape, handle aspect, or locking mechanism.
I noted on another thread that the PM2 has a massive handle relative to its size and some people hate it and others love it. I love it because it gives incredible control. The G10 is grippy but not overly aggressive, the traction is good, and it contours well to the entire hand. For prolonged usage, this is much more comfortable than a standard sized handle on that style blade and it really reduces fatigue.
The Compression Lock it uses is strong, simple, and very easy to clean. Like a FN SCAR, it can get incredibly dirty and neglected and still perform flawlessly. Most people find it to be very easy to operate, and like the frame lock, it is a good mechanism that accounts for normal wear over years or decades of usage.
The blade is in a shape that mimics the "leaf" style blade Spyderco has used on a few knives past which many knife nuts find to be their favorite utility folders. The Lil Temperance is an example here. The blade 'drops' in a uniform fashion, the edge itself keeps on a relatively stable plane, and unlike most knives, sharpening on a single angle will give a very even length bevel (most production folders are going to be thicker at the tip and upsweep and thinner of the belly is hollowed). This makes sharpening easy, as well as reprofiling, or if the user wants to turn the knife into a 'zero grind'. It's also a great blade to grind a micobevel on and there are a lot of success stories there. The tip is also a plus because it maintains enough metal on it to be tough, but the grind is very even in tapering and it maintains that "needle style" tip that many people love because of its fine-work abilities. The Delica and Endura 3 had a similar tip to this, and it has advantages for fine cutting.
The PM2 adds (over the PM original) a better pocket clip that keeps the knife comfortable in carry despite its size. And while this is a bigger knife and a tough knife, it is unusually light. For daily carry, that's a big plus. Robust hardware also helps the long-term usage.
Since introduction, we have seen many of the finest steels made be used on the PM2. Still, the base S30V is a great performer and the design of the blade and hardening allows it to really maximize S30V's potential.
But some people also really dislike the knife, so there is a lot of personal preference with this model having such unusual design features.