I really love this franchise and here's my ranking

FD - 9/10 - great and original storyline, acting, deaths, everything

FD 2 - 10/10 - I know, many people will disagree with this rank but it's my own opinion. First of all, death scenes were shocking and really impressive, Second, this part includes many adult characters who showed great acting compared to talentless teens from FD 3, 4 and 5

FD 3 - 3/10 - very boring. Solarium scene was the only decent death. That's all plus the leading actress was sooooooo annoying

FD 4 - 3/10 - another amateur FD movie with idiotic deaths and horrible acting

FD 5 - 6/10 - this one looked more or less good compared to previous 2 films.