300cc vs 600cc bike?

in the middle of talking about my thoughts on a 300cc starter bike and a super sport 600cc. I have had both for a few months now and without a doubt respect the 300 just as much as the 600, but i also somewhat get a dirt bike feel. The 2016 Kawasaki Ninja 300 is worth the $4,900 msrp if you are looking for a long term commuter in the city, but if you have some experience on 2-wheels or are doing more highway commuting or even a hobby, i would suggest a 600. You can always grow into a bike but what happens when you grow out of one?