Hi Chall,

Styles: hands-down, the PSR S900. You have great styles and access to the vast style community of converted styles from competitive boards.

Intros/Variations/Endings: Again, plenty on the 900. They are also very fluid, which is a great plus when using repeatedly during your style playing.

Fade out: 900 has it.

Song library: Build what you want and throw it on a stick for easy loading (external hard drive).

Also: Has audio recording, great speakers, nice colored screen and more....

Good luck and this is only my opinion.

zuki