Sure it is a good movie, but I don't understand why would people exaggerate so much about it!
All the "lessons" a 23 year-old guy is supposed to learn from the movie, has now turned into such a cliche in 2019.
And who's acting can you people claim to be "great" or "masterpiece"!!! Take Pacino for example, the rule is just to simple to play in GF1, impossible to compare it with great rules of him as in Scarface, Heat, Devil's Advocate, etc.
This movie DOES NOT show Al Pacino's art at acting, NOT EVEN MARLON BRANDO's, it just because of Brando's make up.