Thanks Ben , I see its the earlier version , still a nice impressive 6inch refractor and the BD series were amongst the best , consistent good quality .
As said if AP is your gig and your ED80 will keep you going for years and as you have a 10 inch Dob for visual already I think you would be better putting $550 into your AP pursuits , wont go far
tho ( been there and done that , strictly visual these days
) but hey its your money .
Can you talk to the owner and see if he/she is willing to post an ad. here on IIS ( thru you perhaps ? ) as I think it will sell fast at that price .
Does it come with any accessories ?
Brian.