There has been a lot of hype over Suicide Squad coming out ... it looked super interesting, so of course I couldn't wait to see it. When I finally saw the movie, I was ... disappointed. Trailers gave the impression that Suicide Squad was an action movie, but there wasn't really that much action. In fact, if not for Harley Quinn, this movie probably wouldn't have been worth the time it took to watch it.
Currently I am assuming that Suicide Squad will be like so many movies before it - initially very disappointing, because of all of the hype, but eventually becoming a movie I really like (with enough watching). When a movie is talked up enough, it becomes hard for it to do anything other than let you down. (Kind of like when you read a book with a really hot character, but when the movie comes out the actor or actress isn't nearly as hot as the character you created to fill the role in your mind).
The relationship between Harley and the Joker was complex, and I loved the flashbacks that provided some backstory into the couple. Harley did make several jokes about mental illness, however, so if that is an offensive topic for you then maybe avoid this one. The way she did it was comedic, but could affect some more than others.
I kind of wish they had developed some of the characters and their relationships more (like Deadshot and his daughter), but it was okay as is. It just could have been better.
All in all, I liked Suicide Squad as long as I don't watch it with expectations that are too high. Pretty much ignore anything people have said about the movie until after you watch and form your own opinion. Then you aren't as likely to be disappointed. Enjoy!