Unanswerable question. "Best" depends on what your selection factors are. Price? Durability? And, as others commented, for what type of tool?
Rolls Royce may be the "best" car manufacturer, but not if you need a small, affordable car for your son/daughter to take to college.
One thing I've noticed about the portable power tool manufacturers is that they traditionally each had a tool or two that whupped the market. Often, their other tools were competitive, but not necessarily great. Milwaukee made the best sawzall, Porter-Cable (with its Model 100 and Model 690) made the best router, and so on. Makita's cordless drills were unstoppable; I have one that's long since obsolete, but still going. On the other hand, their corded drills, sawzalls, and non-plunge routers were nothing to write home about. Those are my opinions, by the way; you may differ.