In quality, this show is not bad, but is neither good. It's watchable and entertaining, but not a big deal. There are a lot of unfunny jokes, mediocre acting, shallow storylines, designated heroes, mishandled romance and unlikeable characters. The only redeeming character is Spencer, but in comedy.
About it's classification, it's not a grave case, but there are some things to have into account. Carly and Sam often behave in a immoral way, but they rarely have consequences about this and are treated as heroines. There is too much toilet humor. The adult characters are treated as scapegoats of humor. There is a bit of sexy stuff (and unsexy counting Gibby's shirtless scenes and Spencer when is naked (don't worry, it's not sexualized nor frequent)), like Carly or Sam. There is swearing to some extent.