The movie was exactly what I expected, perhaps with the exception of Kim Basinger who looks smoking hot at an age when most women need hearing aids and false teeth. You have these two old boxers who have had a grudge for 30 years, since they had to fight each other, but the fight was canceled. The film is all about they getting over it via a box match. The fact that they did that after 30 years (time in which neither really had a life) makes it spicier, but basically, that's just the sprinkling on the cake.
I can't say that I got inspired by the movie or anything, but it felt more real than many of the genre, probably because of all the history of the characters making them deeper, meatier. Most movies of this kind use cardboard roles that mean nothing to anyone, like the obe played by Kevin Hart. Even Kim Basinger's role was a typical cliché, the woman that has always loved a man, waiting for him no matter how boneheaded he is.
Bottom line: aside the old actors, this was a typical sports match thing. They train, they say their piece, they fight. Also, except some marketing lines about iPads and some "going viral" lines, this could have just as well been a 70's movie. Robert de Niro was a strange casting for a boxer, but he finally played a role I liked him in since... forever. And Sly Stallone brings a lot more melancholy in this film than in any of the Expendables.