Wow. Thank you all for the quick replies. I used to own a tyros2, i sold it, now i intend to buy an sx600 or sx700. I intend to play few songs, so i use it as a beginner,intermediate, but i still want it to sound good. Im interested especially on synthpopduo style because i play a few modern talking songs which im very fond of (brother louie, with a little love, heaven will know, you're my heart, chery chery lady) but this style i know existed on tyros5 and now it is on sx900. I was wondering if for my beginner level the sx600 is enough, thats why i asked because i still want styles and voices to sound great.
Another question, this time off-topic, is if i can somehow connect the sx600/sx700 to a computer which has an audio interface (audient id4) and a m-audio midi keyboard on usb so on my monitor speakers i can hear both the yamaha and the vsti played by m-audio. This way i can add more voices to the mix, especially for some songs i play (oxygene4, aurora nova, vanghelis) keeping in the same time the style advantage of yamaha because using a daw/vsti i dont know if i can to play styles, only midi tracks to play along but it is not the same thing since playing using a style gives me more control, more freedom. I still like the freedom of vsti but without the backing style accompaniament of an arranger, not that good.
@BogdanH, i heard about revoicing a style but maybe this is hard, im a beginner, dont know if i can be up to this task (i read here on the forum that there is an option built in the sx600 to change style parameters voices drums, style creator i guess it was the name)