Tons of music, challenging, and just tons of fun to play. Even for a beginner as myself it was well worth the import.
If you have seen videos on you tube they are undoubtedly intimidating. Though when you actually get your hands on the game the songs you get in 4 button mode are very good for a beginner to pick up and learn the ropes of the game. I started doing easy songs but slowly I progressed to harder songs as my skill level increased. It is one of those games where you just get better over time.
There is tons of music to listen to from Korean versions of R&B, Jazzy Funk, pop, Dance/Techno, rock. Some songs are sang in Korean, a lot of the more western beats though have accompanying English lyrics. 120 songs in all, to which you unlock many of them. On top of that you can level up your "DJ", leveling up gives you access to new items and songs. On top of that you earn gold to unlock these new items. Unlocking songs is self explanatory but unlocking other items like "notes" or a "dj board" change the ascetics of the game and give you stat boosts. There are also built in achievement system where you earn titles which you can take online and brag about. On top of that you can unlock 2 difficulty modes, 7 key and 8 key modes over time.
There are 4 modes of play, Mission Mode, Stage Mode, Freestyle, and Network. Mission mode gives you a set list of songs per missions and certain objectives to complete(such as accuracy ratings). The missions themselves can be very tough especially as you just start out but over time you will get good enough to complete most of them. They give you nice bonuses for completing each missions such as extra gear to buy and the such. Stage mode is basically 4 stages with a list of songs you can personally choose from in each stage. Completing stage mode nets you nice exp and gold, while failing a mission in mission mode gives you nothing. Stage mode is good if you want to progress your level further as well. Free Style, is basically stage mode but you have a list of every song you currently own and can play it as you feel. Network mode is the online vs component. Even though opponents are in Korea I never once lagged out.
Just overall it is a very fun game and definitely worth your purchase.