I think it depends more on the efficiency of your own FFP as opposed to the alliance as a whole.
The only serious FF relationship I've ever had is with OK+, and they used to be pretty mediocre till about 2005, but I've not had a single problem since.
That's with the exception of miles for hotels/car rentals, which I never seem to manage. Good job they tend to be a pitiful amount so I don't care about them.