35 hp in a lawn mower?! That is more than we used to have in swathers to cut the crops. I'm shocked every time I see the prices of new lawnmowers. For that kind of money I want to get a hay conditioner that can at least pay back the investment. I like cutting the yard/lawn and probably spend a good many hours each summer on the old John Deere 111 that my dad bought used at least 25 years ago. They built them to last back then. It doesn't owe me a thing but I'm too cheap to replace it until its worn out. 
Take a ride along in this video from a few years ago.
https://www.youtube.com/watch?v=lhi9dyeXOmY