Hi Burr,
Great idea!

When Adobe introduced 3dpdf I thought it was a brilliant feature for the same reasons Grendel mentions, for conveying designs more clearly in a portable 3d format that almost anyone can open.

I did investigate it further when first introduced, for business purposes you could probably justify the US$700 but for the occasional user it was a big investment just for the 3dpdf stuff.

To have a plugin for MoI at $50 would be very attractive, I would buy it at a drop of a hat but now I have purchased Simlab I don't really need it and it came with the Luxion renderer which sealed the deal for me, but not everyone will have the $149 for Simlab and your right, who knows what they will be charging after the intro price, maybe wait after the promo and see what price Simlab will be, going by their plugin price of $95, your $50 estimate is very competitive.

Cheers