Whenever I want to check out some new items of equipment, be it lenses, flashes, tripods or bags, my first port of call on the internet is always fredmiranda.com
I like this site because it is not just about lab testing the equipment, it is all about personal opinions of many users, all of whom use the kit in different ways and therefore can give you a good spectrum of experience on how it performs.
All items are scored for several different criteria and often people post comments and sometimes example images. Also, the average price paid and overall rating are excellent quick indicators of items which are proving to be particularly popular or disappointing.
I recommend having a look over it when considering a new purchase, especially when you are looking to spend a couple of hundred pounds or dollars... or yen, or euros....