Here is my experience..
I've owned all three basically.
2015 Yamaha Viper MTX with ice age rails (Same Arctic Cat chassis as Alpha or any other M8000)
2016 Polaris SKS 800
2017 Ski-doo Gen 4 850 With a bunch of grip n rip braces.
So I hit a buried guard rail on my viper. I was doing about 60km/h (40MPH?) and hit the guard rail and got tossed about 10 feet from the sled. The sled flipped and landed on its side. I thought for sure my sled was going to require some serious work to get back on the snow.. I checked it all out, and all I bent was a tie-rod. I could have easily heated it up and straightened it out.
The Polaris was the manager's demo. So I'm not sure what had happened while he owned it. However I rode it the entire year and didn't hit anything. One day I went for a ride off trail just looking for new play areas, and just taking my time.. not taking any chances as I was by myself. On the trail ride back home my ski went way off to the side.. I stopped and found that the bushing that goes through the bottom a-arm to bolt it on to the frame was broken. I don't know why it fell apart.. I was told I must have hit something.. At this point I was almost afraid to ride it. I didn't hit anything.. and it fell apart. So I sold it, this was just one of the issues I had with it..
The gen 4 was a left over 17. and like you I was afraid after seeing all the carnage online. It was a steal of a deal, brand new from the dealer at 7999 USD 9999 Canadian. So I bought it and immediately ordered grip n rip bracing and and some ice age rail braces. I can confidently say I'm not afraid of hitting stuff with this set-up.

I've done a fair amount of stupid s*** on this sled and its still showing no wear.. minus the crinkled bumper, duct taped plastic and dented a-arm.. I would 100% recommend grip n rip to anyone with a 2017. I know in 18 they added a brace.. If it were me, I'd put the kit on any new Ski-doo gen 4 without hesitation.
So in summary. The Arctic Cat is built stout from the factory, Polaris can't take a hit, and the Ski-doo is bullet-proof after you spend about 200-300 in bracing.
This is all my own personal experience, yours may vary.