The Artmix board appears to be two sided from the highres pics I have on file. The size of the thing cut down to just a PDS bus slot multiplier would still be a consideration for two sided protoboards.
trag, got linkage to your explanation?
I can't seem to turn it up. I found this which mentions it back in 2008.
http://68kmla.org/forums/viewtopic.php?p=51475#p51475
It could be that I posted it before the board crash, or I may have posted it over at AppleFritter.
It boiled down to an analysis of what just the raw parts cost in small quantities and even though there isn't a lot going on on that board, it's still probably $20 worth of parts not counting the circuit board. The circuit board is big, so even if it is two layer, it may be another $20 by itself. And I'm pretty sure that Seed Studio wasn't around when he had those made. Then add it assembly cost for a small run, or cost of time to do it himself, plus storage. Handling sales and mailing them out, while always good news, is also a time consuming effort.
In the case of the SE/30 PDS adapter, apparently he had to have a large run made at once, so he also has time cost of money, and the risk that he won't sell enough to pay his costs. It's tough. When you don't know the size of your market, and you must buy 500 of something, in order to buy any of them, do you then sell them for (total cost/500) X (1 + % profit)? Or do you worry that you might not sell them all and so sell them for (total cost / 250) X (1 + % profit)? Realizing that the latter higher price will lower your rate of sales.
It sounds like the Monster is being run in smaller batches, so his risk cost may not factor into it. However, smaller runs usually means higher costs all around.
I think he has a very business-like pricing structure. I doubt that he's loosing money, but he's not profiteering either.