The bic pen exploit is old news. Years old. I don't know if any major u-lock manufacturer uses that cylindrical key setup anymore. There are also many threads on this topic in the Forums already, partly because of the bic pen drama.

Like OP said, all locks can be defeated. Using several different type of locks helps, as they require different tools to break. All those locks and chains also mean a lot of weight, and a lot of money. Not everyone wants to haul many kgs of locks with them, and not all bikes and all circumstances justify hugely expensive locks.

I don't think an absolute "best of the best" lock exists. You'll have to settle for a compromise that's best for you, your bike, your budget, your local theft situation. And always lock next to a bike with worse locks than yours.

--J