Just a general comment so no need to quote... I see no problem pricing single models collectively more expensive than books. Consider a book a "bulk discount." Also, the labor invested in creating, drawing, and editing even a single model's diagrams is far more than is ever recouped by the author, even with the higher price per model. Figure that the more specialized and the more complex the model, the smaller your buyer base, and the less likely you are to make anything off the sale of a handful of a model instructions.
While I do love the free access to many goods and services on the Internet, I fear it gives people a sense of entitlement to get everything for free no matter what. Like people who complain about Facebook. I've had bizarre, intense arguments with people who won't spend $5 for an app that will deliver so much more value. Or the people I offer legit files and photos to - who whine about paying $10 for Dropbox so I can share more than 2gig at a time. They honestly feel that I should waste hours of my time moving and removing files in 2gb increments so they don't have to pony up $10 bucks. People forget that creating and producing a *professional quality* product in terms of diagrams takes many, many hours, and they're kidding themselves if they think paying 8$ for a diagram is going to make ANY creator rich. -- Sent from my Android phone with K-9 Mail. Please excuse my brevity.