The 3 to 5 canes on hybrid teas doesn't always hold true for floribunda's. Less pruning required. Opening the centers, crossing and rubbing or groweing where you don't want them. Left completely alone they will still be beautiful in bloom. However, as they get older the job becomes harder to do so shape them now.
Few people ask about size when buying roses.
It's sad to see someone whack a rose that is too tall for it's spot and then complain that it doesn't produce. Touch of Class, American Spirit, and Peace are three that don't like to be cut back hard. Olympiad, Fragrant Cloud, and Color Magic are some that do better with harder pruning. These are roses I have and ahve tried these different techniques. Hedge roses like Simplicity can be left at the height you prefer although cleaning out some is recommended.