If you've never tried a VR headset, don't put one on expecting crisp HD resolution. The resolution and pixel density leave something to be desired. I imagine these will be the first things addressed in the next generation of headsets. But until then, you will notice a slight screen door effect and some pixelation, usually when reading small text or looking at something in the distance. But don't let that discourage you; during gameplay, when you start focusing on the game rather than the tech, those things tend to melt away.

You'll also notice circular glare on the lenses during high-contrast scenes (i.e., bright object on dark background), but again I usually forget about it when I'm actually playing. The above image, taken from roadtovr.com, is an extreme case, and makes it look worse than it actually is.

The tracking system is nearly flawless. I've never lost tracking on the headset or either controller during gameplay. I have experienced hitches in the framerate on 2 or 3 occasions, but I think that was based on the performance of the game; not the tracking system. In any case, it was only for a brief moment, and not enough to cause any discomfort.