Grand Prix 500
Join Date: Sep 2008
Location: West Lawn, PA
The Thunderbird is going on it's fourth year of production. Most of the maintenance issues have been identified and ironed out (minor at that). The biggest cost is for the replacement of rear tires over the lifetime of the bike.
The Diavel is in it's second year of production or half the production life of the Thunderbird. Check the Ducati forums as suggested by Draeger to see what ongoing maintenance issues there are. With any new bike there are bound to be a few issues. Check to see what the opinions are concerning dealer service, parts availability, and after market items before making a decision.
The cost alone for the initial purchase will favor the Tbird, but either way you're going to get an AWESOME ride.
Good luck w/ your purchase.
Let us know how it turned out.