When you get any tunes (generic or custom) you will need to specify what you car is ie. confirm it is an XR6T, manual or auto, etc. Remember these same boxes can be used to edit XR8's, etc, which obviosuly require completely different programs to the XR6T! CAPA upgrade their generic tunes reasonably regularly and you can always ask them to flash in the latest version for your car. Even if you are using a generic 8psi tune, trust me, you will NOT be disappointed with the result. As others have said though, if running the 10psi map, make sure your plugs are gapped and, if you're in the least bit worried about how the car is running, get your AFR's double checked on a dyno, just to be safe (again remembering that you may not necessarily hear detonation unless it's quite severe). Of course, custom tuning is the way to go but I reckon the generic CAPA tunes are pretty good these days (you may have heard stories about surging with the old 10psi generic tunes but that seems to have been sorted out now). Good luck, and let us know how you go!