Yup I own one. I even waited until the second year of production. Still didn't do enough research.
The engine itself will last for 20000 miles. Just like any other Yami. The rest of the sled not so much. First thing I did was take off the stock skis and put on AC skis. There is not even ten feet of wear on the stickers. Did not like the AC skis either even after trying many combinations of carbides. After much research went with Mohawks with most aggressive carbide they offer. I don't run studs and they are just right. If I had any studs they would also push. Added BOP belt guard so when belt blew it would not take out belly pan. This is important because if you do take out the belly pan you are done for the year because there are no replacement parts on this continent. This also goes for chaincase parts. The chaincase is a flawed design that is prone to failure. There are pages and pages on Totallyamaha about this. It was flawed in 17 and nothing has ever been addressed. For 2021 it is the same.
The drive axle design is also flawed. The bearing next to the brake rotor turns with the driveshaft and wears out prematurely. Also a known issue dating back to 2017. Nothing has ever been done to address it. Also many pages of attention on Totallyamaha.
Stockers and tuned up sleds share these common and known issues. I have never tuned my sled. It is bone stock. There is 3500 miles on it and I would not dare to ride it alone for 10 miles. It is a time bomb.
As far as 200 horse it is a pooch. In stock form it is not that quick or that fast. I have always had big horses. It is not that much faster than a Pol 850. It is not any quicker up to 100. Whoever gets the better launch wins. It is however 175 lbs heavier than a Pol 850.
To those of you who say it doesn't feel that much heavier when you are riding it you are idiots. It is a top heavy front heavy slug that will wear you out if you try to keep up with a lighter sled in the Twisties. I have ridden it for 3500 miles. I know this to be true. No amount of suspension tuning or rider ability or expensive shock absorbers can make up for 175 lbs. Physics always wins.
Yamaha or rather AC builds big heavy expensive junk. I have been on Yamis since the 2003 RX ton. Which by the way was faster on absolute top end than a stock Sidewinder. But I have had enough. Good luck to anyone buying a Sidewinder. You will need it.