Sigma 150-500mm, Which Backpack?

Having just bought a Sigma APO 150-500mm lens, I'm in need of a new bag. I would like a sling but think the weight will now be excessive for one shoulder, so I'm thinking of a backpack and have seen this Hama Daytour 180 link

Does anyone have any experience of this bag or other reasonably priced bags that will take the Sigma lens while attached to the camera body (total length 32cm).

Any advice gratefully accepted, Thanks.

I find a wheelbarrow works quite well

I got a second hand ccs gladstone which works well for the sigma 50-500

Dave

Thanks guys.

Dave, I'm really looking for more of a sling of backpack, but thanks.

I don't pack this lens attached to the camera because of the strain on the flange/mount...or am I being too cautious?

As long as the camera and lens are supported properly in the bag there shouldn't be any strain on the mount.

I found the Kata T-214 Torso Pack takes both my newly purchased 150-500 and the DA300, comfortably, but not attached to the camera. I generally use a CCS warthog slr pouch for the camera, much quicker to get out but not with the 150-500 attached!

The Kata is a sling type and no problem when full. Holds the lenses nice and secure within the bag and no problem when moving from back to front of the body. Easy to get the big lens out and in.

Works well for me but not sure how much they are new. I bought mine second hand.

Thank you everyone for your help and advice.

Danny, Great review, I think it probably exceeds my needs, I don't think I really need to be able to transport a laptop at the same time. I am in Aylesbury, thanks for taking the time to post and really appreciate your offer.