This card isn’t really breakable in any major way, but it’s going to provide an extra few points of power and toughness, and those always mean something. The Podium also gives you the ability to dig for and search out other legendary creatures. It’s an X ability, meaning you’d have to pay a good deal of mana to dig deeply enough to make the effect worth it unless you run a good deal of top-deck manipulation. But it's a solid utility card in a Commander deck heavy on Legendary Creatures.
As far as Constructed play-ability is concerned, there aren't enough Legendary creatures that will be main-boarded to make this card worth running. It’s one of those cards created first and foremost for flavor, possibly created with an eye for being played in Commander. In Commander, there are Legendary Creature heavy builds, especially led by Captain Sisay that benefit with this card. Decks that feature a great many Kamigawa Legends or some far-out 5-color deck that runs the best legends from all around the color pie can use it to great advantage, as well. Otherwise, it's just a bulk rare with a splashy cool ability.