I get the 2-4-1 voucher every year; normally have two available at any given time....so unfortunately occasionally have to use one "cheaply"
though with RFS you actually get a pretty sweet deal - did a week in Lanzarote (LGW-ACE-LGW) for a grand total of £90 for two of us to fly Club Europe return - OK CE is not an incredible product, but it made for a nice enough start & end to the trip and over a 4.5 hour flight we got a full hot meal and some more space - Mrs Ratypus was reasonably impressed which is what counts!