I have been traveling and stopped at every shop I could find without success.
This does raise some interesting questions, though.
For BLMA, I presume you made a certain percentage over the orders as most mfgs do. Did the popularity of these surprise you? Did bigger pre-orders suggest you should make 15% more rather than your (?) standard 10% more?
As to Walthers, I wouldn't necessarily assume its them. I have been shorted by the LHS before (not just one) and usually when I start digging into the reason, its the shop itself either didn't:
1. put in all the orders, due to a poor system (or I hear) an owner who just doesn't trust N scale buyers.
2. couldn't get all they wanted because they were behind on their payments to the wholesalers, or
3. just gave one away to a "better customer" assuming at least one person who ordered would decide that they didn't want theirs (actually ordering a few less than ordered based on past cancellation experiences to keep inventory down)
Personal note, I knew they would be good, but had a self imposed buying gag order on myself. Somehow, once I found out I couldn't get a set, naturally, I wanted it all the more. Great model. I am sure we will get more runs.
