If you take two identical cars, one with auto, the other with manual.. the auto car will most likely beat the manual off the line... not always.. but usually. The manual however will have a higher top end (less parasitic loss from all that crap in the auto tranny).
If you could shift perfectly every time the manual might take the auto off the line.. but perfect shifts all the time is a BIG "if"!... if you shift too late you will probably hit a rev limiter that most newer cars have built in, or if you shift too soon you will not be in the power band.. (both of these scenarios take the motor out of power band!).
The auto tranny is computer controlled.. it shifts at the right time all the time! The manual tranny is "you controlled".. in my opinion a lot more fun!
Been having a blast with my new car!