There is more wear than just on the valvetrain. Piston rings anyone?
I'm not exactly sure how a "pushrod" engine has more wear on the valvetrain than a OHC engine. The "chains" are driven off the crank and are turning the cam. Close to the same lifts/durations...
I don't think anyone said there is going to be "excessive" wear...
The higher the rpms, the more engine braking...
Sure there is a fine line in to much gear and to little gear where it causes the engine to bog. Engine hp/tq effects this as well and how well it makes it during beginning of the powerband at cruise.
Your average 99+ with 3:27's holds the rpms fine...96-98's have a bit harder time keeping the bogging feeling from leaving.
I cant wait to see how 3.73s feel in my car they came intoday just waiting on my rearend to get here which should be here tmw so..But I think 3.73s is just great for a dd..