ZT 0460 Sinkevich

No wiggle and stayed locked with about 10 or 15 whacks.

and I can't picture many scenarios where some portion of my index finger isn't mashing against the lock during use.

I did have a ZT years ago in which the clip screws/bolts actually broke a portion of the grip material and the clip came off...

ZT knives are ok but not that great and yes, they fail several tests.

I have a ZT 301 that doesn't fail this "test", so it is obvious from my sample size that no ZT has this problem.

Seriously, none of the 5 knives I actually carry and use have this problem, and if they did I'd send them back to the factory.

Okay, I caved... All caught up on Larry Correia and Stephen Hunter novels, so out of sheer boredom, I had a "whackfest!" None of my ZTs, 0450, 0900, 0770, and the flawed 0620, failed. Of course, the wife unit came in to see what the ruckus was immediately judged me to be under the influence (or if I had whacked my head). In her words, "Who in their right mind does that?"

No YouTube so believe it or not...

I currently own over 35 ZT’s also Spyderco,Benchmade,ESEE,Lion Steele,CRKT,Microtec and the list goes on i carry a 0630cf daily and use it in finish Carpentry there are several ways to open a knife either light and girly or manly confident and intentional you will get different lockups and should be about 40% this is where failure can take place if too light i feel the spine test like all interweb boobs is useless nothing is perfect by useing your tools as they are designed to be there arent any problems if it fails most manufacturers have outstanding customer service,know your tools and train often who wants to try the toaster test

Whack test is pretty standard for folders with liner locks.
I've seen more than a few with issues-some very high end models.
Would I buy one? Not a chance.
Would the manufacturer give you grief for returning or complaining? No way.