Thing is a one way won't be half the price of the RT. I highly doubt it. It will likely be more. Add airfare and it's an even more expensive trip. Well I'm glad I at least got to do it in Oct 2012. It was heaven.
A one-way will be 10 nights vs. 14 or 15 nights for the roundtrip. If both were offered (and I doubt they would be) - I think the roundtrip would still cost more.