Honestly? Most fun I've ever had on an MMO.
The gameplay of the only gameplay styles I have ever enjoyed in an mmo, as they've evolved the hack'n'slash style to fit the superhero setting. It's not a shallow point and click style with repetetive and boring gameplay.
Your character is allowed 8 skills out at a time rather then proving an overwhelming limitless array of skills to bombard your screen. The classes are generally balanced with few exceptions but nothing absolutely gamechanging. One satisfying element of the game is that you can make anything viable if you're good at it. You literally have a choice and won't face negative consequences for choosing a rebelious build.
The pvp in the game is absolutely amazing. Party up with some buds, queue up from wherever you are, and jump into whichever gamestyle you want to play; whether you're feeling CTF or King of the Hill.
Overall, extremely fun with friends whether you're a free, premium, or legendary member. No gamechanging differences between the membership options. Seriously recommend this game to anyone, from the most hardcore dc fans, to the most casual gamers.