the best rock band (i'm gonna assume we're talking on a basic rock grnre thing here...) technically ha got to be dream theater, i mean, besides their singer, they have got to be the most jam packed with talent band o all time, john petrucci, john myung, mike portnoy, and jordan rudees? c'mon, name a band with more technical flawlessness...
that being said, if ya wanna go on the whole essence of a band hing, thing there is no clear winner, but i'd vote for metallica or the beatles anyday.