I have heard that some vendors for the Diablosport Predator will include one or two free re-tunes, which would be nice if you are planning on doing heavier mods later. Also a couple inexpensive mods that I hear will improve the overall "feel" would be a DMD and some (poly) bushings and mounts.
Oh yeah, if the car is a weekend warrior, you might also want to think about giving it a little laughing gas to help you down the strip.
Just my .02
