As an afterthought, from what I have been told, and what I have Googled . Subaru's, Are in class by themselves when it comes to this sort of thing. Other make AWD's are much more forgiving.
I am not trying to go for the cheapest option. However if I don't have to replace the other 3 tires, and can just have them shave the one, that would seem smart to me.
I am just concerned that shaving a tire would create a whole new set of problems. ( as in tread, would be affected, and screw up handling in an emergency situation) Which is why, I posted, to gain wisdom from you guys.
I very much appreciate anyone who takes the time to post and for your opinion