The difference of the true sled builds from 15-20 years ago to the sleds of today. The sled builds from 15-20 years ago determined the size of your balls. The sleds of today determine your riding skill because you have no balls and ride in the trees.
This I will say. A build today is nothing like a build 15-20 years ago. And a lot of the builds from back in the day will still lay a licken on todays stuff.