How Accurate is Camquest?

I have the camquest and it calculates 410 HP as my peak on my 360. I also tried another piece of software that cost several hundred dollars and has much more specific choices like it has a selection for magnum and another for magnum R/T heads plus it has selctions for most of the more popular intake manifolds. This software calculates the HP of my 360 at 398.

Based on knowing 1/4 mile trap speed and the weigh of the car with me in it I can estimate crank HP. Doing it this way I come up with 370 HP. Thats likely a little low since I have traction issues and typically get 2.2 to 2.4 sec. 60' times and the car is still accelerating at the end of the 1/4.