The Doo bars last a long,long time.I stick with what works.The bars that came on my new mxz 500 lasted about 300 miles.I asked the dealer what the deal was,he said the bars that come on a new sled are "starter bars" and don't last at all,so I bought the Bombardier replacement bars and they lasted 2600 miles,and were still good when I traded the sled in last spring.