The Yamaha styles are the most impressive (And there are 1000s out there) however if you regularly listen to live bands, then you soon realise that they are the least realistic out of the 4 big brands. (Hence I have never rated them)

Roland used to be the best for realism; however they seemed to have dropped the ball of late with the top spot being taken by Korg.

If you like lively styles (Which are typical of the European versions) then Ketron take a lot of beating.

As always these are purely my personal opinions, and should not be taken as an attack on any particular manufacture. (Some users can sometimes take it personally)

Bill