Mattraks for RTV900

I happened across a used set of Mattraks.  I had thought a bit about buying some tracks (might be fun here in Maine) but didn't think I could justify the expense.  What would be a fair price and are there other brands that might be better?   thanks!   first post  here...

 A new set of Mattracks sell for around 7500 bucks. I have a set of Soucy's on mine aand the price is about the same. Soucy's are heavyer also.