Lamborghinis, Ferraris etc. really aren't that fast. They are more legend than reality. They are 12 second cars and make in the 400-500hp range for the most part. You pay for the privilege of driving an exotic. A stage 5 or higher car with the right driver could really change the race dramatically.
In a recent tuner car article in Motor Trend they had all kinds of super exotic tuner cars like the Venom Twin Turbo and Lingenfelter Twin Turbo both making over 1000hp and they were 11 second cars.