Trust your dentist rather than a product. Whichever dentist you are comfortable with, let them decide which company they prefer. I use Lava which I like best. Again in Lava there are various types. Then there are cheaper options available, again Zirconia. Zenostar from Vivadent is good no doubt but does his regular Lab have that material - a Lab that he is comfortable with. Express your desire for a particular brand but let the dentist have a say in it too. After all he is responsible for your teeth.

ivoclar zirconia is better