I see video of people playing music with backings and different instrument. Many times press buttons above keyboard and I'm not sure what is the function. PX-S3000 has 88 key and small light size which is good. He is also cheaper. Casio has accompany rhythms and different instrument, but I don't know if he can play performance like this with sufficient backing track. Does it have enough feature to do? Or is required Korg?