In first gear, hammering it past 7000 rpm is all right, because so little time is spent from 6500 to 7200 rpm, and you're slightly up in torque when you go into second. However, in the higher gears, it's your choice. Personally, I feel shifting at 6500 or slightly before is more optimal-too much time is spent in an area where the horsepower is dropping if I try any higher rpm in the taller gears.
In the case of acceleration testing, I took both the AA and stock setups to the maximum engine speeds in first gear, hitting 60 in second. To keep the results fair, both tests were done at our testing location with an altitude of 500 ft above sea level and 72F. Baseline tests yielded 0-to-60-mph times averaging 6.76 sec. With the AA setup, the average runs were 6.49 sec.-over a 0.25-sec. difference.
When the owner got his car back, he was nothing but thrilled. He called me, as well as AA, excited as I've ever heard him, and raved about how much more he loves his car.