I don't think anyone can realistically expect EVERY style in any arranger to be ALL good. Especially as what even MAKES a style 'good' varies so radically from player to player.

All one can realistically ask for is CONSISTENCY...

And I definitely hear that with Yamaha styles.

I guess a lot depends on whether you want SOME styles ridiculously better than others, and some styles a bit ho-hum (and hopefully, your taste is to the styles that are the best), or you are prepared that ALL the styles be just a LITTLE ho-hum, with nothing that stands head and shoulders past the rest, but nothing that sucks compared to the rest...

I have to confess, I'm more into consistency, myself, or at least into nice easy editing tools so that you can achieve that consistency yourself without a boatload of work...