UFO has a slight deformity in the front fender that needs to be corrected after install with a bungy cord or tape over the front of fender and pull it to the left. Polisprots I have never had a problem with, Cemoto are good but not made for all models, and Acerbis are good also. The choice is really yours and who makes it for your bike.
EDIT:
I use UFO for all white or black
Polisport for OEM blue/white
Acerbis is overpriced for what it is and fit/finish/quality is the same IMO
My personal YZ is Black UFO
My sons is White UFO
Zero problems with either except the slight curve to the right that is corrected over night.