If you do purchase a set of adjustable cam gears make sure they are AEM, Skunk 2, HKS, not a set of no name brand gears off Ebay!

Its hard to say what gains you would achieve, as tink said what he gained on his car, you might not gain on yours.

For the money I doubt I would be worrying unless you were chasing every last KW and you had money to burn........