For people who only came around in the D/p era, yes, it very well might be.
For others who came at the start of Ex or middle of Ex, no, probably not.
Dragon fronteirs and Legend maker where massive sets, with awesome cards.
DF: Flygon ex, Altaria ex, dragonite ex, kingdra ex, Mew*, Gardy ex, meganuim d, Feraligator d, Nidoqueen d, Rayquaza ex and a Copy cat, buffer peice and holon mentor reprint.
^ That set made a format. We had Flygod, Draggy ex occasionally, Gardy ex's, Megagator, LOADS of decks with nidoqueen as there engine, Mew* was in next to every deck, Kingdra swarm.
LM: This also made quite alot of awesomness with : Banette ex, Arcanine ex, Dustox , flygon ex, Kabutops, lapras and Gengar. Most revolving around react energy.
It very well may be the best Dp set, but not the best ever.