One thing I think I can usefully add to this thread is that the "Force Coupler" feature in this engine actually works and is pretty complicated/subtle. For a description I can't improve on Lionel's manual and in particular the left page in this image:
I don't think I have heard the "crunch" sound yet. However I can say from my own experience that this feature does accurately sense the load on the engine - including that it goes up when pulling a long or particularly heavy consist around a curve. I can't say that this was a selling point of this engine for me because (1) I was more interested in the smoke features and (2) it's on by default and overrides manual EFX settings, which I have got used to adjusting myself. But it works according to the manual description.
This is the most ingenious as well as reliable VL engine Lionel has put out since the GE Evo "Green Fleet" model of several years back. Or at least IMHO it is.
Downside: The traction tires on this engine seem prone to detach when pulling any heavy load. In my case it was just four NYC Superliner passenger cars, which are aluminum and pretty weighty but roll smoothly along the track. Fortunately in my case the tire did not shred and I was able to re-seat it in the wheel without too much difficulty. I think however that I will use plastic cars behind this engine for now on.
