Magazine road tests of the 2004 Crossfire when it 1st came out put the automatic at 15.18sec. in the 1/4 mile, and 14.7 for the 6spd.
I think Garry ran a 14.7sec. in his automatic (with no other mods) using a single NeedsWings CAI.
Doesn't sound like much of an improvement, but in the 1/4 mile it is.
Lot's of people have built their own, but I don't think anybody has built a better mouse trap.