Hi there and welcome to the forum, nice to see another J300 owner out there.
Sorry to hear you are have clutch judder, this seems to be a common fault although mine is fine at the moment.
Its a 2017 special edition and i have covered 1,300 miles on it. I think these scooters are great to ride as they are not too heavy, previous scooters were a an650 Burgman and a 500 tmax. both were ok but too heavy in traffic.