I think it would be a great idea to have one Adaptive Payments plugin, so you could switch between one or the other, perhaps we could put it out there for someone to do, and split the cost between those that would want it.
I found some good resources here, that might help get someone started, obviously it will need some work to convert it for nopCommerce, but you actually get three options with Adaptive payments, "Simple Single Payment", "Chained Payments" and "Parallel Payments", so you could just use this plugin for all your PayPal needs.
I have not been able to find any MVC examples but this might be a good start here.
