I have an 02' 750 & I did a lot of research on this topic & I decided to go with the Techlusion TFI Box. It is the lowest cost method to improve the air/fuel mixture. The FIM chip is reather costly and the PCIII is less that the FIM but double the cost of the TFI box. It is very easy to install & fine tune on the dyno. I had mine installed & tuned @ the dealer & the total cost was $250.
http://www.techlusion.us/home.htm
http://www.techlusion.us/home.htm