My understanding is that these are meant for developing nations, and the lower cost is an incentive for inducing education over there. Although it may be cheaper in the short term, in the long term you may be jeopardizing the business model and thus reducing developing nations' ability to obtain textbooks. Just throwing that out there.

I've heard a little about those editions but don't know much about them, so I think you might have some user education necessary. But it sounds great on the whole.