I do not need styles. Acoustic sounds are all I need.
Since Yamaha MO6 is in the same price range, I did some search on the net, and others say acoustic sounds on MO6 are better than those on M50, while most in general say M50 is a better workstation.
I looked for videos on youtube, and I did not find interesting guitar sounds on MO6 or M50, and for XS6 which I think should be much better than MO6 and M50, I am not sure if I can say acoustic guitar sounds are better compared to PA500.
So it looks that guitar sounds are not the same on PA500 and M50.