If buying private youll get a good idea of its history by the owner...service history essential...but all the 2nd hand dukes ive bought have had a shed load of receipts/paperwork, all neatly filed..the sign of a fastidious owner !!!
The fact that it is pretty much standard is a good sign too (praps you can lend it to performance bikes magazine for ther photoshoot as even they cant find a std one !!!)
Cheers and best of luck..you wont go back to the dark side once youve had a duke !!
Nat