Sweet, can't wait to hear your impression of him and see some pics
The problem with hairing the Hasbro piece is he was a but too big proportion wise to begin with, and there is not much you can dremmel off since the sculpted fur is pretty short and the rubber/plastic is not that thick. So adding fur onto it will always make it look better.
I think a similar thing would happen with the Sideshow piece, sure you could grind it down assuming it's not hollow (although sometimes they are) but man would that be a lot of work.