Ok, there's so much talk about knives on these boards but I've been meaning to ask a somewhat specific question - what is the strongest folding knife available off the shelf (no one-of-a-kind custom knives, please) that you have ever handled personally?

Strongest in this case is defined primarily as having a safe, solid lock - something that comes close to a fixed blade knife, even in terms of lateral strength (eg. prying) where folders are usually the weakest.

The reason I'm asking is that a lot of folders are marketed as super strong these days but IMHO very few could come close to a fixed blade at the end of the day. So I wonder what combination of lock and blade design is the strongest in your experience.

The CRKT models that include the AutoLAWKS system have to be close, in the sense that there is a lock and then a lock that locks the lock. In that case, it is very difficult to force the lock. That said, I know that some of their Chinese-made models feel weaker to me than the Taiwanese versions.
The CRKT M16-13Z made in Taiwan that I own would stand up to anything that a fixed blade knife would, I believe.

"something that comes close to a fixed blade knife, even in terms of lateral strength (eg. prying) ", "off the shelf"? None.

Even a very strong semi custom like a Chris Reeve Sebenza is going to loosen eventually with lateral prying. That is something some fixed blades do not do well.

Take prying out of the equation and I'd go with a Sebenza's framelock or an axis lock such as that on The RSK Mk1 and many other Benchmade knives. It's a very strong lock.

Benchmade 520 is mighty strong with the axis lock, but you pay for it with the weight of the handles.

I'll stick with my Barry Wood Folder, As far as I know the've never had a failure causing them the close up on fingers

Ka-Bar's got some pretty tough folders. I own a Ka-Bar Mule, and I reviewed it on this forum some time ago. It is one tough folder, and the Dozier family are also pretty tough folders from Ka-Bar. I abused mine pretty rigorously when I got it, and the lock held firm. For the money, it is a good investment.

Don't own it, but the EXTREMA RATIO RAO is mighty tough

http://www.extremaratioknivesdivision.eu/inglese/military/rao.htm
http://www.knifetests.com/erraophotos.html
http://www.knifetests.com/erraotest.html

mighty

Zero Tolerance folders are VERY solid and I have recently picked up 2 folders from 5.11 Tactical that are VERY heavy duty.

Thanks for the feedback! Having made several knives myself I'm well aware that every folder has a number of structural limtiations. Nonetheless, it's interesting to compare some of the newer "heavy duty" folders out there to see if they can live up to the hype.

Right now the verdict seems to be that the AXIS lock is pretty solid, I'm sure the AutoLAWKS is an advantage as well. However, I wonder if the lock design per se is as important as the actual implementation. Seeing that the Kabar Mule is "just" a lockback but apparently still a very good performer.

BTW, I know a guy who bought an Extrema Ratio folder. Turned out the knife was built like a tank. So overbuilt in fact that it was pretty much useless as a cutter. Something along the lines of a sharpened folding crowbar, not necessarily the best of both worlds.

I've always hear that lockbacks are the strongest "lock." That being said, my Cold Steel has some pretty good lateral play. The AXIS lock by benchmade, as are the AutoLAWKS, are supposed to be very strong.