[Down N Dirty]

As I was getting ready to buy a new Gryphon for my 06, 5.4 and I came across a used one for sale. It has 3 custom tunes for a truck that has just about the same mods I already have. He put his truck back to the stock setting before removing the Gryphon, and has supplied the HEX code. A couple of questions, does anyone see any issues with buying a used Gryphon, I believe the individual to be a very honest person. Anything special I need to do before installing it, and last, should I re-register it under my name with PHP.
Thanks for your input.