Update: My ZW-L was returned last week from Lionel, repaired good as new.
Unfortunately, the chopped wave just beats, rattles and grinds the heck out of my PW equipment. I have now hooked up an LW transformer next to the ZW-L with a toggle switch. Whenever I switch over to the LW, the motors and E-units instantly quiet right down and engines run smoothly.
Don't get me wrong, the ZW-L looks great with the fancy meters and cool lights, even if it's useless to me for running trains smoothly.
Now, if I could only find someone who could design a device which was capable of converting a chopped wave to a sine wave. Then I could actually use my ZW-L to run some trains! I might start a separate thread on that topic to explore the possibility.