Gitzo GT2541 vs GT1542T for hiking and exploring

Which tripod do you have? The GT1542T or the GT2542T?

Could you tell me a little bit about sturdiness in windy environments? What ball head are you using?

I usually strap my tripod to the side of my backpack. When I go backpacking, my backpack is huge and there's enough space.

When I just go hiking, I'm using either the LowePro Sport 200 AW (put the tripod either on the side or at the bottom of the backpack) or a bigger LowePro bag (forgot the model name, I think it was CompuRover), which actually has a tripod carrying system...