In my opinion, one of the best, in terms of function. I like everything about the 710, blade shape, lock, ergonomics, and looks. The only shortcoming of the knife is the blade steel. An M-2 710 would be a hard package to beat. But the best folder in the world? I don't know. It is a more comfortable knife than the Sebenza, and bigger. The Benza is stronger and has better cutting geometry.
The Darrel Ralph Apogee is hell for strong, and is closer to the 710 for ergos than the Sebenza, and cuts better. I go with the Apogee for the best folder in the world for me.
The REKAT Pioneer is extremely ergonomic, is way strong and reliable, but is rather small and has inconsistant edge geometry. I've had three of 'em, and all had pretty thick edges, i.e. were not very efficient cutters.
The Wood/Irie swing lock is a marvel of strength, design, symmetry, and precision. They are not one-handers though.
A new front runner in the beauty, efficiency, strength, and precision realm is the SpeedTech Synergy.
So it is really hard to say that the 710 is the best in the world, but it is a contender, will be an even more serious contender with an M-2 blade. That is saying a lot for a production blade. I would feel very good about saying it is the best production folder in the world.