I, II and III are all totally awesome. III isn't as driven by drama as the first two, but the Thunderlips fight is killer, and Clubber Lang plays an awesome bad ass.
IV was great at the time, but it is so 80s in retrospect, and not necessarily in a good way.
V wasn't good, but it did have one of the best lines from any Rocky flick - "Yo, you knock him down, why don't you try knocking me down now." Great line, and perfect delivery by Stallone, conveying how angry and serious Rocky was after Tommy sucker punched Paulie.
Rocky Balboa was good, but didn't have the rewatchability of the first three.
I am sure I will see Creed, but I can't see me going out of my way to do so.