Well, I am thrifty so take that into account, but I'd go with the used one if it looks like it has been well taken care of. You will save $2500 cash and that will buy pretty much all the farkels you can think of with plenty of money still left over. As for the $1000 in accessories you'd theoretically miss out on, how many of those would you get if you actually had to pay for them?
Either way is not a bad deal though - I guess it all boils down to if you want new or not.
"The turd follows the fart as surely as the rain follows the plow."