Thanks a lot for your opinions, my friends.
Reading you, I see some ways to go respect to these shortcomings of Yamahas.

About key feel, nothing may be done: only to buy a midi controler keyboard.

About styles, I may use OMB, or use converted styles, and so, to have richer and more elaborate styles. But I don't know if converted styles retain the dynamic and varied musicality of Roland or Korg styles. I played some converted Roland styles into PSR3000 and they sounded not so well as I would like and as they sounded in my old Roland.

I was thinking that, ten years after I had my old Roland, the best arranger kb for the buck would be a lot better. It is better in some aspects, but not in styles and musicality.

Yes, as you say, there are ways to go. But why must I do all of that work for to have a kb wich sounds out the box as I want? Why must I to buy a midi controler for to have a decent keys, to use converted styles for to have rich and not repetitve styles?

Why Yamaha can't do it by self? Yes, better keys and more musical styles cost more money, but... other manufacturers do it.

As some of you said, I may spend a lot of time exploring its Yam potential, tweaking and revoicing the styles and the sounds, and finally, the yammie will sound every bit as good as any other board.

By the fact, others keyboards have similar potential too, but they seem to sound more musical out the box without all this work.

Well, sorry if my words may be a few offensive to yamaha. It was only a emotional reaction to a disappointment.