Perhaps not, unless you have a discerning eye or are a real techie.
Most of the features claimed for the Power Bridge chassis are refinements or improvements over the previous chassis (which was called the Fleetwood Power chassis), increasing strength and storage bay size, larger water tanks, better utility bay layout, etc. And there have been further refinements since the introduction in mid 2008 as well. So while the improvements are real and worthwhile, you may not notice night & day difference between a 2008 and a 2009.
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2004 American Tradition; 2014 Buick LaCRosse
Homebase in the Ocala Nat'l Forest near Ocala, FL