I have a Sebenza. Think of an integral lock as a liner lock without the handle slabs. When you grip an integral lock folder, your hand becomes the safety. It can't open as long as you are holding it, the tighter the better.
With a liner lock, the outer slab keeps you from squeezing down on the liner to hold it in place, but you can press against it from the other side, when you're gripping it tightly, and release it accidentally.
Personally, I've never found lockbacks to open accidentally, especially the ones with the lock at the rear. So they are pretty safe, too.
I just got a Benchmade 730 Ares. Not only is the axis lock super secure, it's ambidextrous, too, which is a safety feature of a sort.