My rear tire is going to need to be replaced soon and I was looking at the Metzler Lazertec. I'm currently running a Bridgestone BT45 on the back and a Bridgestone Exedra on the front (original tire). The Kawasaki dealer did not recommend doing this. They said stick with the BT45 or go back to the Exedra (both Bridgestones). The tires are stock sizes. I still don't really understand why you can't mix tires. And I don't mean mixing bias and radial. Are the Lazertec's going to run longer than the BT45's? Suggestions? Thanks.