To my mind horsepower (or poor 0-60 time) is just a bit of disadvantages. The main thing is driving style. The only advantage of auto is in heavy trafic jams

The only one... I wont start explaining how can you drive with manual and not with auto in daily driving, in dragging, in track, about the lag and etc. Auto is for lazy people, who just need to get from spot A to spot B and thats it. Manual is for drivers, who likes cars.
If you are asking such a question, just stay with automatic.
P.S. I am not talking about hi tech multi clutch gearboxes with shifter near steering wheel (Ferrari for example

) or future gearboxes. I am talking about 1990-2011. I think there is no need to talk about earlier auto at all