I've been running the X3 for two seasons now. I've had it in just about every snow condition at this point, and the only time it's been a bummer has been on real wind blown hard pack, when I almost came down a hill backwards.
Obviously, the track is not meant for that type of snow.
I haven't ridden the 3" PC so I can't compare the two. The X3 is heavier, but less expensive.
All I know is I still have all my lugs, and I wouldn't go back to the 2.6" track.
Downhill braking is improved
You can slow down on a hill, pick your line through the trees, get back on the throttle and dig out of some sticky situations
On the other hand, the track is heavier (X3)
Overheating on a trail becomes an issue, but normally isn't a problem if you put the scratchers down and try to hit some fresher snow when you see it
Between the '16 front end and the 3" track, I'm not sure which is the better mod. Both make quite a difference.