If you have high ground, not much for tight corners, easy driveway approaches, the best bang for the buck is any make tractor. They cost less to fix, can be used for other things then grooming and are more durable. Tractors without tracks are the very cheapest to run. Look for a tracker with at least 100 hp. More than 100 hp if it has tracks.
The big three tracked machines makers are Trucker, Bombardier and Trail Bullies (Piston Bully). These groomers are the best for swampy areas, steep side hills, high driveway approaches and tight corners. The newer the groomer, the more power and better fuel mileage you’ll get. Resale on these types of groomers is the worst, but it also provides you better deal on used ones. New track units are going to be in the $135,000.00 to $160,000.00 price range. Look for 150hp or more on a tracked machine.
When it comes to drags, the length and width would directly depend on how much power you have and how wide and twisty your trails are.
As far who makes the best makes the best groomers or Drags, it’s like asking what’s better a Ford or Chevy.