Diamondkote?

[topo4u2]

I just bought a 2005 Silverado and the dealer sold me the dimaond kote under coating. For the doors and underhood they used a yellow wax spray and for the underbody they used a black tar like spray. Has anyone had any experience with this undercoating..good or bad? They supposedly provided a 10 year warranty. There claim to fame was that all the other sprays are oil based and can destroy rubber materials.