Now I don't have one of his tensioners, so I'm not speaking from personal experience.

My feeling, is that if you are having vibration issues, then it would be worthwhile. If you have your belt set up correctly to begin with though, it should last a very long time with little or no thought given to it... IMHO
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2010 Blue RT Audio & Convenience model Se-5 transmision. Dealer-added foglights, accent LEDs and extra speakers. Some RTS chrome windshield, front spoiler and top trunk trim, RTS frunklight and frunk liner, Top Trunk liner, Chrome lower air deflector, fendertip LED bulbs and ISCI floorboards added by yours truly...