Broadway at the Beach is a fun spot ... it is all connected and there will likely be events outside as well. From my experience Margaritaville tends to be more crowded -- so if you go go early, but I always have a great time there. I haven't been inside Hard Rock, but I have been to the bars around it and had a good time.
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Girl, go to both!!! Barhop and enjoy the fireworks they have at midnight. But if you have to choos ejust one go with Margaritaville. I've been to both and have had a blast at Margaritaville, I felt a little uptight each time I went to Hard Rock. Hope you ahve a great holiday.
Re: Question
I just saw this in the news today. There is some info on both Margaritaville & Hard Rock on NYE.
https://www.wmbfnews.com/story/16353278/new-years-eve-events-at-broadway-at-the-beach