My 2x72 has a gas spring, gas strut, whatever you'd like to call it. Works a treat. It's got a couple advantages over a spring, namely constant force regardless of displacement (spring is approximately linear), and yes they do some damping which I would consider good. The gas in it will resist going from one side to the other the faster you shove it, so they can hold steadier under variable loads than a spring, which might make a difference every time the damn splice flies past.
As for the nature of that dampening, it depends entirely on the manufacture of the strut. Some have a constant bypass, meaning the internal orifice allowing gas to pass from one side to the other never changes, while others do taper down towards the end, making it harder to move in either direction near full extension. The amount of bypass also determines how "stiff" it is (but not the force applied, that's defined by internal pressure and difference between rod and bore diameter).
