It doesn't matter to me that the boxing choreography is shit and pretty much all the boxing is crap, they're just great films to watch. The first two have great heart, and the third was great in it's own right - it's only with the fourth that the shit hit the fan. I still watch that one occasionally, but it's a love letter from Stallone to himself and it shows. It's way over the top in it's cheese and silly elements, and the fifth...?
The fifth is hard to watch. Not because it's a bad film - I wouldn't call it a great one, but I also wouldn't say it is bad - but because we'd come to care for those characters and to see them sink so low was a punch right to the heart. How many times had we seen Rocky get back up after getting knocked down so hard, only for him to receive his toughest blow yet? Watching them to have to scrape a living yet again was hard, and then of course you have the betrayal from Tommy just all adding up for a hell of a depressing film. I recently gave my copy away, it's that depressing.