05-09 GT Auto or Manual

Just wondering some about the Difference in times between Auto and Manual Mustangs of these years. They have droped in price because of the new 5.0s and people are trading them in so they can be gotten at pretty good price around here in Texas. I could get either but I have heard that when they changed the auto from what I consider the Slow 4 speed(have in my current mustang) to a 5 speed it helped shift time considerable. Auto would be nicer in my part of city but I don't want to wait on auto shift speeds like i do in my current car if I can do it my self so much faster. Any input is welcome thanks.