In France a retailer similar to BestBuy has a "Lab"[1] that usually has objective reviews, using a set of standards to compare items of the same category. Here's an example: [2], you can scroll to the conclusion to see the grades, but you also have an explanation behind it.
[1] http://labo.fnac.com/
[2] http://labo.fnac.com/video-photo-numerique/appareil-photo-re...