I have several liner locks, and a few framelocks, but it is the linerlock that's in question so I'll limit my comments to it. I've had and used linerlock knives since they first became available in the 80's. I've never had a knife to accidently close due to a linerlock unlocking while in use. I've a couple though that the lock did not properly work. A push-relax-push-relax motion on the back of the blade would cause the lock to move to the left of the blade tang and close..........one was a custom. Of course these went back to the place's they came from!
At any rate I learned that giving the locking leaf a little more bend to the right would give it a tighter lockup, and make the lock stiff enough that you pretty much had to make a conscious decision to push it over.
The linerlocks I have are;
PRODUCTION
1. Fallkniven PXL
2. ZT0200 (2)
3. Spyderco Perrin PPT
4. Spyderco Vallotton Subhilt
5. Ontario Hossom Retribution 1
CUSTOM
1. John W. Smith SD-3
2. Mike Irie Model II
3. Dustin Turpin Repentance.
I have no problems with any of the above linerlocks. ALL have had some slight bend added to the locking leaf that has stiffened the lock to my preference.
But the best advice I could give has already been given........treat any knife with a lock like it doesn't have a lock.