Just a question or two.
Why get rid of the 320? I have the X360 and am very happy with it. Other than power steering and hydraulics, is there much difference?
What kind of a beating will you take on the trade?
With the price cuts, customers could just as well buy new instead of a used machine. This could leave the dealer sitting with a used X320. Knowing that, the dealer might not give you the best trade in price.
I am not trying to talk you out of trading, just offering up some ideas.
Is the 320 not doing what you need it to do? If not, you may want to go bigger, as in an X500 or X700.
Just some food for thought. Good luck.