I guess I was lucky finding a Starmate- (in fact, #515 purchased from the Spyderco table at one of the shows)
I like the Starmate for it's great handle shape and overall good looks. And the crazy sharp CPM 440V blade is a huge plus too. But I prefer to actually carry my 800 AFCK, though, as it rides lower in my pocket. The Terzuola locks up nicer with a solid 'pop' every time, whereas on my AFCK, the lock kind of stutters and scratches it's way over to the base of the blade. To the BM's credit- it does lock solidly every time, just not as smoothly.
The linerless G-10 handle on the Starmate is light, while still being plenty strong I'm sure. I think I like the comparative heft of the AFCK a little better. One thing that for me gives the 'edge' (HA!) to the AFCK is the pocket clip. On the Spydie there's the Military (new) style clip, all big and shiny. And it leaves a lot of knife sticking up over the pocket edge.
Not to say either of these wouldn't tear the living *&%! out of anything you needed them to when properly implemented- just these kinds of considerations are important to the cubical warrior like myself.
On the blades: Tie. Both have opened tons of mail and dispatched many fruits and vegetables with nary a wimper. Rigorous yes, I know, I use my knives hard.
Handles: Advantage AFCK. The curve fits my hand well. Feels sturdy. Terzuola holds well, feels basically rectangular though.
Lock-up: Advantage Starmate. Way smoother and makes a slick popping noise when you open it, even if you slowly open it- every time.
In-pocket-carry: Advantage AFCK. Rides lower. Starmate clip says "look at me, I'm a knife, and I'm going to hurt you".
Overall looks: Advantage Starmate. Has that Bob T. flavor about it. Very nice.
Since I don't (usually) have uses for my knives that would actually make me worry about handle flex, edge geometry, and steel superiority, I probably can't judge them as 'tacticals' persay. I'm sure they'd both fare well. If I had to pick, I'd get the AFCK again because it's darn nice for the price.
To borrow a phrase, I'm just not a super secret recon seal ninja. Both are great knives. They separate household matter with aplomb.
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