Some of the comparisons to other knives and makers seem "off" or even a little obtuse to me.
I've owned a lot of custom tac/utility knives in the past 10 years. Onion, Carson, Mayo, Ralph, Chew, Boguszewski, Terzuola, Obenauf, Blackwood, Emerson...lots of stuff.
Many of these had unbelievable fit/finish, or insanely smooth flipping action, or mirror-polished blades with hair-popping edges, wild anodizing and engraving, etc.
For me, I've found that much of that stuff ends up being useless/undesirable in a tac/utility that I plan to use.
Personally, I've decided that I should only buy utility-type knives that I would actually use, and that if I want safe queen/art knives I should buy art knives (nothing wrong with that either).
Based on what I think the knife was intended to do, I think the XM-18 is a home-run.
I love Boguszewskis (have owned over 20 of them). The fit/finish and flipping action is insane. For me it's not the knife to use out in the yard cutting burlap off of root balls or something. If you would, then more power to you. I was doing just that with an XM-18 this weekend and the knife is no worse for it. They are different knives.
If the XM-18 had a thin mirror polished edge, anodized bolsters and clip, a roller bearing pivot, etc, then it wouldn't be the same knife and it would have been sitting in my drawer (nothing wrong with that).
Buy a tool for what it was intended to do -- not what you wish it was.