@Mark W , have you considered scaling those ties to N for the C40 rail?
I have, but to keep the reasons simple, the cost for N scale ties would far far outweigh the novelty. If I'm being completely honest, I doubt I'll get any takers on the Z Scale ties, simply because it'll be about twice the cost of current products, and then the end user has to deal with a lot of fuss in sliding the rail in the fragile spike heads too. Sounds like I'm almost talking myself out of releasing these in Z!
Nonetheless, I designed them for my own use, they work, and they look damn good too once painted and ballasted (below). So, since all the design work is done, no reason not to let others have at them. I won't even be putting a markup on them.