Nope haven't had any problems with the current headset... My first upgrade might be a stem or handlebars... Actually scratch that probably tires. I have no problem with the xdx that come with it in most situations, just wish they had a little more aggressive tread at times for the sandy Phoenix area terrain. I experienced a pinch flat on some downhill I wouldn't even consider very hardcore while running 25ish PSI tubeless too, which could be have been my fault *shrug*
Out of curiosity, why do you want a new headset? And what other upgrades have you already made?
Out of curiosity, why do you want a new headset? And what other upgrades have you already made?