What do you guys think about really large tires for trials practice? I have a line on two sizes of large road construction equipment tires. One is 7 ft tall and 3 ft wide, and the other is 6 ft tall and 2.5 ft wide. They are huge tires. Must weight well over a 1000lbs. I was kind of thinking about cutting the 7ft tire in half and putting the two halves together to form an upright double half tire obstacle, and the 6 ft tire laid down flat. What do you guys think? Too big? Or just Right? They are both $150 each as well.