See
http://alpo-astronomy.org/mars/articles/FILTERS1.HTM
Colour filters are useful in enhancing contrast of surface and cloud features of planets. Different colours will bring out different features so all colours are useful. E.g. A light blue filter gives the Great Red Spot on Jupiter are darker appearance making it easier to see. A red filter will give blue festoons are darker appearance.
Some filters are quite dense and require larger apertures to maintain brightness at the higher powers but most with the exception of possibly #47 work well with 6-8" aperture. Sometimes the contrast enhancement of detail is subtle and sometimes dramatic, it just depends on the colour of the feature and the colour of the filter being used.