One quick comment on the John GS Eprom chips...
I sent the specs for my 2003 GS Adventure to John in Greece and requested that he recommend the best chip for my particular bike. It took a day or two longer than I had anticipated, but John said be patient, as he was writing me the very latest chip. The delivery package arrived, and contained not one chip but two! A Stage 5 chip and also a Stage 8. The gist of the instructions was S5 for better mid-range boost and economy, or S8 for all out performance.
I fitted the S5 chip very easily in around 40 minutes, all done, it is not a complex procedure at all, and I have to say that the change in performance characteristics has been dramatic. It always felt to me that the bike was being held back or restrained in some way, and the new chip has changed this completely. There is no surge, no more on/off as you close the throttle, both up-shifts and down-shifts are SO much smoother, and as others have commented, you are generally a gear higher than you would normally be.
Johns product is excellent, his friendly service is excellent, and I cannot recommend changing the Eprom highly enough. You will not regret it!
Italian-GSer