Well, you all have short memories. I've never any a Korg or Roland fail either, but plenty of hiccups on all brands, including Yamaha.
They had VH parameters wrong on the PSR2000 and never corrected them, although they emailed a full-page work-around so you could sort of make it work as it was supposed to.
They had multiple screen failures with PSR S900.
I can dig up more, but I remember these right off.