I'll defer the answers to this question to the racing forum since MMZ-Timelord and I just spent the weekend running a very tough technical road course against a bunch of different cars. MMZ is still in Buttonwillow and won't get back to San Francisco till tomorrow, so I'll wait to let him chime in on this question.
Just watch the Racing Forum over the next week or so, you'll see some great photos & video and also get an earful about how the stock SRT6 does against a race prepped limited and a bunch of other cars, including the C6 Corvette.
PS: My car is so much faster than I am !!!