It will come pre-loaded with a generic performance tune. If you decide you want a custom tune for your specific car and mods there are several Diablo dealers who can perform this service in addtion to local dyno shops.
Agree . . . used or new Diablo will not warranty a programmer bought from ebay.
I bought one for my Son from a group buy through a dealer with a warranty. I put it in his '04 GT and when I went back to make some changes for gears and what not after the install it kept misloading the program. I would have to uninstall and reinstall a few times before it would finally take the program. I talked to Diablo about it and they said send it to them and they would check it out. I did and within 3 days they sent me a brand new one as a replacement, no questions, no hassles. So, with that said it was well worth not buying off of ebay.