I'll be asinine enough to say it, but Final Fantasy VI beats Final Fantasy VII in almost every aspect.
Final Fantasy V, on the other hand, is less stimulating. It has a great battle system (the job system also seen on Final Fantasy III and in the Final Fantasy Tactics series), probably the best in the series, but it also slightly lacks in many other departments. The story here is askew in the sense that it has the typical Final Fantasy plot: go save the crystals. The music here is also just missing that touch that Final Fantasies (mainly IV and VI) have brought before. Nonetheless, being compared to Final Fantasy VI (which it is packaged with) is a huge downfall, because this only brings about rough comparisons with the two.
Thus, at the end of the day, this is a great package for any role-playing game fan. Final Fantasy VI is truly a masterpiece, and Final Fantasy V is sporting the best Final Fantasy battle system to date. Add in all of the little extra goodies, the computer generated cut scenes interjected throughout, and the two-for-one deal, and one gets a real nice deal here.