Ok, I called my friend at Denon LA, and he said that they expect the upgrade to be $800 installed; $500 for the board, and $300 for the install charge. This raises an interesting question: You can buy the 5800 right now (heck, it was in the HTF Hardware For Sale for $1900!) online and via ebay for ~$1800-2000. You buy that, send it in for the board upgrade, and you now have the 5803.. but you paid $2700 or less. Can someone give me a reason -NOT- to do this in comparison to buying a 5803 outright ($4300?) That's a $1600 difference!