Mine is going in today for the same set up. But after doing research and following the threads here, and on other forums, I made the decision to go with a custom chip to start with. I have talked to numerous people who have had to have KB send them multiple chips to get it correct. Everyone I talked to always was very happy with their customer service, and finally got it correct in the end. I though, do have the time to be going back and forth to the shop four or five times to get it correct. Sure it could be dead nuts on the first time, but I'm not taking any chances. I want to drop it off, have them tune it on the dyno, pick it up in a couple of days and be done.
I have an '03 S281, and am hoping for numbers like 00s281sc368.