Here is another question if you had to choose a 2013 with all the upgrades done except for the sprocket, cam belt, and with stock exhausts or 2015/2016 in stock form which would you choose. What does the '16 need that Morgan hadn't done?
It would depend on condition and price.
Factor in the sprocket and cambelt cost for the 2013 model and then pick the one which you prefer.
Put it another way, I wouldn't swap my 2013 for a 2016 of identical spec.