Actually very good...
In the game there are different levels you can try and speed. I forgot what level its called but i do the hardest one with the fastest speed (only on some songs). It is very entertaining to watch and play. Btw it is a great and fun way to exercise. Oh i almost forgot to mention that you can beat this game in one night so it really isnt that long but there are many songs to select so you may never get bored.
If you are looking for a game that can give you a workout but still have fun or to keep people entertained at a party well then i would highly recommend DDR Max 2.