I think I'd go with the established publishers (EK, TBR, TPR). Yes it's going to be different with new subjects but you can still use these publishers for the existing subjects and then supplement some of the newer stuff. I heard EK is coming out with a brand new set very soon including 2015 updates.
The MCAT really hasn't changed much at all on the existing subjects for years and years, you could pick up an old set from the big publishers and be fine.