This is an interesting review of lightweight packs which have impressed Jason Klass prior to 2010. Its a good mix of information and may indicate maybe what you should consider when you look at a pack.
Hopefully it’ll give you more of an idea about what to look for and to ask yourself the key question, “Do I actually need that” when being bamboozled by the sales guy and the huge array of goodies and pretty colours you are presented with.
Apart from fit, the most honest question you need to ask yourself is “what do I need the pack for?”. It sounds simple, but I always suggest people take a piece of paper and actually write the answer down. As you do so, it becomes clearer in your mind, the features you need and why, before entering the shop, or trawling the internet.
In this video he looks at the older models, but it is still relevant and a stimulating process to get you thinking.