Depends on who you are I guess. If you're a massive fan of DD and John Taylor was the reason you picked up a bass then I guess it would be worth more to you... or me.
Turns out that the bass is almost definitely not his, John had a look at the bass and is pretty sure it's not his old one. Lucky escape, i got the mail just after I'd bid £850 on it, luckily I was outbid!
- Edit. Damn my keyboard and the sticky c key... the above is now in English