User blog comment:Kogath/Monster Hunter X Discussion/@comment-8874090-20150912212624/@comment-184612-20150912213733

Guild Style can equip 2 Hunter Arts

Striker Style is basically the 2nd gen movesets, but with the ability to equip 3 Hunter Arts, which also have less cooldowns.

Aerial Style can equip 1 Hunter Art, and have a lower chance to mount.

Bushido Style can also only equip 1 Hunter Art, and their moveset has changed as well.