It all depends what you consider best? The best killer is the polar bear. The cutest is probally the koala. The safest big bear to be around is the black bear. The best to watch in the wild "from adistance" is probally the grizzley bear. Again it is dependant on what you are looking for.
I'm going to take a different approach and assume you misspelled bear...in reality, you were asking "what kind of beer is best?"....In which case, I would respond, Guinness!