What I find odd is I don't hear much about head gaskets failing in the US... Maybe Yamaha took pity on us since we have restricted throttles and gave us better head gaskets? Definitely something weird going on there.

As for issues from the factory, most people in the US complain about the cam chain tensioner noise and the clutch being grabby. Most people fix these with a manual cam chain tensioner and buy or piece together a clutch kit. After this it's personal setup and tuning.

Fortunately there are forums where people post about certain issues with bikes or what is really great about them, makes it easier to fix/figure things out.