A friend bought one of those about 5 years ago and asked me about the run in procedure on road. The dealers did not have any advice regarding how to run in the big two stroke, it was set on a milder engine tune in the ECU.
My suggestion was to avoid high revs and drive it on the torque for a while to keep the heat in the engine low and keep the pressure on te piston rings. After riding it home, he called me to say it smoked up the back tyre at about 60km/hr in 5th gear by accident. The power was awsome.
Unfortunately the fuel consumption off road limited its use so he sold it.
As for durability, the 450cc fourstrokes don't last long if you use the power, the valvetrain and heads are quickly demolished and rebuilds are super expensive.
2001 Yamaha Zuma, DR Evo 68 cylinder, Leo Vince TT derestricted, Delorto 17.5 (#98 jet), standard aircleaner, RMS fan, Race CDI, Standard oiler and premix @ 75:1 Shell SX2, Doppler SR3 variator, RMS clutch, RMS R rear shock absorber and Pirelli SL26 tyres.