I have the same camera as Bryan. This year I bought a new Lowe toploader which has a better rain cover.

I carry only one lens and make sure it is relatively light. The case is carried bandolier style over my shoulder. With filters and a spare battery this comes to just over 2 kilograms which I think is worth it if you are really inot your photography. To some extent the weight on your front helps balance the weigt of your pack.

This year I caried a tripod bringing the whole load up to 3.5 kilograms. Perhaps, this is no advisable.

The weather was so bad this year that I hardly used it all!

Still, the sun is bound to shine next year

Hi, carrying one or not is a personal preference. I carried mine this year. After looking for many years for the ideal carrying solution (when using a rucksack) I think i have found it. I use a Spiderpro bracket attached to the belt and a simple silnylon bag draped over the camera - completely unobtrusive and faster than a normal bag. If it wasn't for the weight I wouldnt have known it was there

cheers