I've spent many years carrying around one Lowepro backpack that is simple and easy to use. It has lasted about 12 years so far so that's pretty good going. But it's a different matter when it comes to hiking in the hills or even walking any distance with kit. I trekked through Slovenia into Italy with two bodies and two lenses a few years ago and realised two important things are required:
1. a good pair of walking boots and
2. a really good backpack
The walking boots have been resolved but the backpack took a while - most camera backpacks are really cleverly made with pockets and places for everything, tripod attachments and all sorts of gadgets - but have I been able to find one that actually sits really well on my back? The answer is 'No'. I found my answer in an Osprey women's fit rucksack which sits perfectly into the back and onto the hips. Women are most definitely a different shape to men, but not all camera bag manufacturers have realised this. Osprey, however, have spent much time and energy on their women fit range and now I have two - one larger and one smaller.
The drawback is there are no compartments for cameras, no soft padding between lens. So my solution is small padded bags that protect bodies plus a load of soft pouches for extra lenses. For me, the compromise in packing the camera is well worth the absolute dream of being able to carry kit up a hill without even feeling the weight anymore.
You can see more gear and clothing recommendations on my post here