My favorite lock is the front-lock (similar to the back-lock):
-tough
-reliable
-if the blade has a choil as on the Spyderco models, the knife is really easy to close safely with one hand
-ambidextrous
-it derives from the old back-lock, so it is time-proven:thumbup:
For light-duty folders I also like a well made frame-lock, but only if it has a beefy liner, completely exposed to direct hand pression during the grip & it is made from a company with rock-solid reputation.
For liner-locks after I got a total failure with an italian liner-lock (a Karambit made by FOX knives), I will never buy an other liner-lock.
In my opinion it is not a reliable lock, it is weak and it is not consistent (sometimes the liner stops here others stops there, with front-lock you get constant lock-contact open after open).
In the future I would like to prove an integral/frame-compression-lock , but for now there aren't interesting models on the market (a Spyderco with a titanium frame-compression-lock would be awesome in my opinion, immagine a "Super-manix": one side with black G10 & steel liner the other pure titanium with exposed beefy compressing liner... I' am dreaming

)