with the accelerator floored, an automatic will usually run up to redline before shifting.
Plenty of people, The Mustang was very successful in SCCA competition, Trans Am racing, NASCAR, IMSA, etc.
The current GT-350R will embarrass a fair number of "real performance" cars from Europe.
LOL, most high end supercars will redline at or over 8000 RPM these days, and being close to redline doesn't necessarily mean you're going to be at max HP. Relatively few car's peak HP is at redline. Under the current F1 engine rules for example the maximum engine speed allowed is 15,000 RPM. However most drivers will upshift around 11-12k RPM because of the KERS and turbos they use now, there's little reason to rev the engines that high because most of the power is below 12k RPM these days.