One of the problems of all FFM schemes is how they change by the year, month or day. I used to collect 'Airmiles' [UK branded scheme] but found them such poor value. Wanted a week in The Netherlands.I had the right amount of Airmiles but found their surcharges (since removed, I think) too high.
I then checked the same flight direct with BA and found it cheaper and checked EZY and, unsurprisingly, went with them!
They all change their schemes in subtle ways and you just have to keep an eye out which is another reason why I use them for upgrades not outright purchase.