I understand your frustration but thankfully I've had very good experience with Yamaha. A few months ago I broke a button on my Tyros 2, they charged me $2 to replace the button or $50 to replace the whole button board. Now the screen on my Tyros 3 broke, and it has been replaced for free, even though I had to pay labor unfortunately...

I've had Yamahas for fifteen years and thankfully they've held up very well.