I rode the '16 Cat for a weekend. We also had a '15 XM 163 and my '14 Pro along. The Pro is more fun than the rest, hands down. The Axys is likely a nice improvement, which puts it waaaaay out front IMO.
I hope there aren't any first year issues but, I passed on the first year model due to Polaris' history with such things. I will pick up a '15 holdover, knowing what I am getting. The only thing better on the snow will be the Axys IMO.
I like them well enough stock, just a small riser for my height. Gas, Oil, Ride works for me. I do obsess on them a bit but they are easy to sell all stock, so that's how they stay.