Captain Obvious Moment (COM): Because we know next to nothing about you and what's most important to you, West, all we can really do is speak to our values, and what's important to us. At the end of the day, you are Master of your Domain...so take everything us Knuckleheads say with healthy portion of salt/skepticism/objectivity.
For transparency, I don't own a Delica. I'll touch on why later.
Starting simply, I would rank the three knives you listed this way:
1)PM2
2)Endura
3)Delica
This is why, in no particular order:
-Generally speaking, I buy the knives I want and price, though important, is pretty far down the list of factors...just ask my bank account. For many, its the first thing/priority. Nothing wrong with that at all...there are many, many, many things more important than knives. You can basically buy 2-2.25 Enduras/Delicas for the price of one PM2. Is the PM2 twice the knife of either? I would say no. But because value is lower down on my list of importance, my 1st choice is the PM2.
-Though both are, objectively, great materials for handle, I prefer the look and feel of G10 over FRN; there are G10 Delicas, Enduras and handle upgrades available on the secondary market, but my comments throughout refer to the standard versions.
-I prefer the ergonomics of the PM2. They're all really not that different, honestly, but I like having a forward finger choil, even at the expense of some cutting edge. I also like the longish handle of the PM2. Some decry the negative impact on blade-to-handle ratio, and rightly so in limited instances. But, its never been an issue for me, even though I appreciate knives that are space efficient. The Delica is basically a shrink of the Endura, but the handle loses a bit of height in the process and that makes all the difference to these XL hands. Also with that loss of height comes the sensation that my fingers are crowded up in the first finger groove. A hint of that lingers with the Endura, but the extra handle length gives my digits the option to move back a tad without feeling close to the end of the handle. Yes, I'm picky.
-Some will disagree but...the Compression Lock is way more awesomer than a back lock. Its arguably more interesting. It's easier for
me to actuate. And, who of us PM2 owners don't relish all the silly tricks, games and entainment the CL opens to us? =D
-Before sitting down and comparing them side by side, I didn't realize how close in size the Endura and PM2 are...what, a 1/4" of length? But, the Endura has quite a bit more cutting edge and, coupled with its sleeker/thinnner profile, make it seem much larger to me. Conversely, because the PM2 has more handle and more of a leaf shaped blade, it appears smaller to me. The Delica seems like its short on blade to me. Basically, what I'm saying is that the PM2 is the perfect
size for an EDC knife. IMO.
-S30V is no longer really leading edge, but Spyderco's variety is pretty good, all things considered. VG10 is better than a lot of entry-level steels out there, but still a lil 'Meh' to me. I need to give it another try, if I'm honest...it has some redeeming qualities...but I still say: S30V > VG10. Advantage PM2, especially if you include Sprints.
-As mentioned above, if a color variety is highly important to you, the Endura/Delica siblings are the way to go. The PM2 offers some color options if you include the Sprints, but still not as bold or distinctive as the former. These days, i just want to get away from black. If the knife I want...design and materials...is available in something bold, that's definitely cool. But, I'm never looking specifically for something bright and shiny for myself.
That about sums it up. You're going to buy all of them though...just keeping it real.