CDs,
We just got back from the Summit two weeks ago. I was confused about this, but all those Massanutten resorts are on the same property, so the resort amenities are the same for all. The best way I can describe it is that the various "resorts" are like condo "neighborhoods" in the "town" of Massanutten.
I can't comment on the Condos at Eagle Trace, but I did write a pretty lengthy review of Massanutten here on TUG. Maybe my review of the Summit units can help you decide if Eagle Trace is worth your trade, if they are considered lower in quality? But that of course is subjective.
Expect to drive to everything, and not just a quick two minutes; it is mind-boggling how much acreage this place covers! It's the kind of place where I think it could be really easy to slip into complacency and NOT do a whole lot, since there's no pool right outside your door or anything. IOW, it takes some planning and effort to figure out where you want to go and coordinate where all your family members need to be and how to get them there and back. Also, activities do fill quickly, even in April when it wasn't so busy, so plan your week early.