I had a look through some previous post about bags, but I did not find anything related to bags/backpacks for telephoto lenses with wildlife photography in mind (please correct me if I'm wrong).
At the moment I have Canon EF 100-400mm with Canon 500D, Tamron AF 28-300mm + hoods and sometimes a monopod or tripod.
What I'm looking for is something compact (I do not wish to carry whole "lens store"), comfortable, with easy access to the camera with attached lens, good protection, and ideally some extra space for lunch or other items.
In sling-style bags, the Kata 3N1-30 seems to be very compact or new version of 3N1-35 PL that seems to be more comfortable. Then there are backpacks such as Bug-203 PL (I like the easy access to camera) BumbleBee-222-B UL, Lowepro DryZone 200, Lens Trekker 600 AW II or Nature Trekker AW II
So what are you people using?
I took in consideration David proposal and while bag-hunting in the shops I tried different harnesses with cases attached. David approach would work for me in case that I would be carrying backpack to counterbalance the weight on the front.
However at the end I closed up on my original path for bag. I found that Kata 3N1-30 and 3N1-35 PL are rather robust and almost in the size of BumbleBee-222-B UL. Their smaller sibling Kata 3N1-20 is actually big-enough to fit in camera body attached to 100-400mm lens plus 2 other lenses, with some space on top of the bag in separate compartment. Only downside is no direct way to attach tripod.
I'm sort little disappointed with Lowepro offer only reasonable products been Sling 180 AW and Fastpack 200, but in my opinion they been lacking on equipment protection (thin padding) and comfortability.
At the end of the day I decided to go with Tamrac Evolution 8 (model 5788). This does provide comfort, protection for equipment, chance to attach tripod/monopod and has reasonable price (£80 + delivery in UK).