I'm searching one for reproduce GM, XG Midi and DOC files, mute the piano part, and play it with my acoustic piano.
Can i use this keyboard for this use? Has access to this control with a simple buttom?
Has it got realistics sounds?
(I hope you can understand my English)
Thank you!

The PSR-350 has pretty decent sounds. They are realistic and I think you'll find the quality good for the price. As far as muting tracks.., If memory serves me right there are like 5 or 6 tracks for recording on the 350, and I'm almost positive you can must them as well. It will work with GM, XG, ect. The only thing you might have to do is fine tune the keyboard... Your acoustic and the keyboard may be off slightly with the tuning.. It depends though.. Sometimes you don't have to worry about that, but with some you do...

Squeak

Use a sequencing/notation software (Even Finale Notepad Plus) to control the keyboard and mute/add parts as you see fit while you play any other instruments.

Pedro