As far as durability comparisons go try this with your Remington 700 or your granddads Winchester.
Pull one of them from underneath the rotting corpse of an enemy soldier who's been laying in a rice paddy for a few days. Hose it off with plain water and toss it in your locker for a month in the SE Asian jungle heat and humidity.
Take it to the range, kick the action open because it's rusted shut. Put 120 rounds through it.
Repeat the toss it in the locker part and the 120 rounds part (without cleaning) once a month or so for 11 months.
Then get back to me about it's 'durability'.
The men under his command were reconfiguring a firebase and they were using bulldozers to rearrange the berms. One sweep of one of the dozers revealed the body of a Viet Cong, who had been killed in an assault the previous autumn. The body had been entombed in the dirt of the berm for six months. He was still clutching his AK.
Hackworth pulled the weapon off the body, pulled back the charging handle, and fired off a round. After the weapon had been buried in the jungle for six months.