This may sound odd, but I'm an AFCK-lover and an Ascent-hater.
I find the handle shape of the AFCK very comfortable, enjoy the smooth action and easy one-handed closing of the liner-lock, like the ability to disassemble and clean or modify the knife, and just enjoy its overall balance and feel. Even as a devoted Spyderco fan, I rate it as my favorite folder (4+ years of carrying one may have something to do with this). My only gripe is that the ATS-34 is brittle and difficult to sharpen, a gripe fixed by teh M-2 version (though I must then put up with a coating).
Now take the Ascent. The larger finger-groove destroys the grip for me, and I have yet to meet someone with a 1.5" wide finger. The Zytel handle cannot be disassembled and throws the weight uncomfortably far forward, so the knife feels ready to tip out of your hand. The lockback cannot be closed as easily one-handed, has a rougher action, and on those I have seen (early specimens) has up-and-down play and unlocks easily with pressure on the spine. I cannot consider this knife in the same class as similarly-priced Zytel knives from Spyderco or even Cold Steel.
I'd obviously recommend the AFCK if you can afford it. If you want to stay in the Ascent's price range, look at Spyderco's Endura and Goddard Liteweight, which have better locks, better ergonomics (a personal issue, of course), and are easier to sharpen. The only advantage the Benchmade has over these two is tip-down carry, and if that's a premium you might look at the slightly smaller Calypso Jr. Liteweight which will be out very shortly in excellent VG-10 steel.
It's my opinion that Benchmade has a ways to go before they become a serious player in the Zytel knife market.
-Drew