Mine has a PC IV in it, all tuned and runs good. The previous owner had it dialed in and I'm not going to fix what ain't broke.
However, the big deal now is GuzziDiag. Using your PC to remap the ECU. There many off the shelf tunes that can be downloaded.
Any way, just check it out on Wild Guzzi. All you need is a cable and a laptop. And a little more skill than I have.
http://wildguzzi.com/forum/index.php?topic=69168.0