I see 2 online dealers who have the K4's in stock as of January 19, 2016, so I indicates to me Bachmann did not underestimate the market for these. Of course, this does mean Bachmann still has any in stock; in fact, their online store says sold out for the K4s.
I imagine if enough people took the offer that Roger did Bachmann would start having parts to repair broken models with.
Not really. The MSRP is always going up with each new model, so it is just a matter of giving away something new to replace something old. And the new thing is Bachmann's choice, which means it is likely the current item that they are not selling like hotcakes.
What I mean is that they would then have broken ones they had received back through trade from which they could then harvest parts to repair others.
