Lucario, being exclusive to Toys R Us, is one of the hardest amiibo to find. It kind of bothers me that half the Pokémon characters in the SSB line are store exclusive, making them pretty expensive online if you weren't lucky enough to get a preorder or camp outside the store on launch date. If you're a Pokémon fan, I highly recommend this along with the other SSB Pokémon amiibo.
As for figure itself, Lucario, like Pikachu before, looks a lot like the official Pokémon toys, minus any articulation. The fur he has on his torso is much more detailed than on most other merchandise I've seen of the Aura Pokémon. The supportive plastic keeping Lucario bound to the stand is in an awkward spot, kind of like the ones on Luigi and Captain Falcon. It just seems weird that they went with that choice to put it. They couldn't have put it on his feet or something?
As a fan favorite to both the casual and competitive audiences of Pokémon, Lucario is a nice figure to have. Currently, no other games to my knowledge can use Lucario for a special purpose outside of Smash. Maybe if Pokken Tournament gets a Wii U port with a worldwide release, maybe Lucario, a well as Pikachu (and Charizard, Jigglypuff, Greninja, and Mewtwo if they get confirmed.) can be used for them. Either way, if you're a Pokémon fan or trying to collect 'em all, Lucario is a very nice addition to your team.