The MZ2000 loaded both Technics and Roland styles directly from disk. They all needed some tweaking, and the results varied from fairly good to awful. We converted some Yamaha styles to Roland format, as the MZ did not read Yamaha style files. Much tweaking was needed there as well.
When converting styles, you allways need to tweak them to get good Results, expecting anything different would be overreaching. The same is to be expected from the MZ-X, yes it can load Yamaha styles, but they need to be tweaked for the best results...
The only arranger that has passed this stage is the Varranger that has several different soundsets that replace the orriginal brands soundsets.. And even on Varranger tweaking thos styles will give you better results..
I think Casio support forums will become the place where people will share their converted and eddited styles...