Well they are both very well done servers and are the biggest minecraft servers in the world. HiveMC's highest is almost 10,000 players whereas Hypixel's servers got 8500+. I personally believe hypixel is better, because of more donators, better minigames, more minigames, less lag and a better lobby-joining system. HiveMC is good too, but for me it's definetly hypixel.
My favorite server of all time is Uberminecraft Factions.
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