4120 here with power reverser...only 156 hours on the tractor so far, but no problem with the reverser. Works as advertised. Only thing about it is (and this is probably obvious) don't use it while going faster than say B range in 2nd gear. Otherwise it tends to jerk you around when it reverses or it tears up grass if you're in grass (spins a little). It's not an instant reverse of direction, but it's quick enough that it'll spin or jerk you if you use it in a higher gear.