Finding a durable pair of pants that can withstand the rigors of traveling off trail in heavy brush isn’t easy. Lightweight nylon pants often get shredded quickly, and more durable fabrics like cotton canvas or cordura are heavy and uncomfortable.
I had been using old camouflage pants for bushwhacking for a while, but found the 5.11 Taclite pants. They are a cotton/poly blend fabric, with lots of pockets. I’m a big fan of the bigger thigh pockets that hold small items easily; compasses, GPS, snacks, etc.
The benefit of the cotton/poly fabric is that they are durable while remaining relatively light. The downside is that it will get wet and not dry as easily as a lightweight nylon fabric. In warm weather, this isn’t that much of a concern. I wouldn’t use these pants in weather where I was concerned with hypothermia.
I’ve not used these pants for rock climbing, as I bought them specifically for bushwhacking, so I can’t speak to durability against rock, nor the design of the pockets for wearing a harness.
Another interesting feature of these pants is that they have double layer knees. This, in and of itself, is a great feature as it adds substantially to the durability. There is a small slot in the knees that you can slide a neoprene knee pad into. If you like to take photos like I do, kneeling a lot is common. In addition, they help pad the leg against the brush and thorns. However, they really make the pants much hotter in warm weather.
So, in short, these are a great pair of pants for off trail use.