I don't really have much experience racing, but in my opinion, if shifting slows you down, you're not driving properly.. I can up/down shift both my 1776cc '72 beetle, and my Challenger without it slowing me up, you just have to be good on the timing..

Yes, auto's are more consistent and the torqueflite was an awesome tranny (worked on a few of them in high school) but while I'm still a "dumb kid" I will never own a muscle car with an automatic.. hell, I absolutely hate driving the work vehicles cause they're all autos, just not my thing while i've still got decently working knees...