I agree with Ericka.
I do a lot of travel between Europe and the US. Economy usually costs around €600. Business (were I ever to pay for it!) would cost around €4,000. So: I pay for coach, and I use miles for Business or First. As a UA1P or 1K, 4 RTs in Economy (for €2,400) get me enough miles to do an RT in Business. Seems like a good deal to me...