Hmm, good discussion.
I tested a number of developer and film combinations a number of years ago, and landed on PMK Pyro for for most of my personal developing (mainly, but not exclusively, sheet films), though I rarely see any of the vaunted claims other than "fine grain". Hutchings claims the big advantage to it is that you can "let the highlights go", getting some 8 or 9 zones (I participated in a Pyro workshop with him early this century). I don't particularly like handling the stuff, the negs can be trying to print through, and I find them exasperatingly difficult to judge for fine art print potential until proofed. But when it works, it works spectacularly.
I now regret not testing XTOL at that time, as I had not used it for many years. But I know it as an excellent general purpose developer, which I think I may have short-changed. I am going to try it again and compare directly to PMK.