Costco may have a good warranty on tires but its too bad their service center sucks.
They are slow as hell and I'm not very trusting of their workers. Tire Factory has really great prices without skimping on other things.
Here you get great service and they're realistic with the timing, also you can always head across the street to get a grinder from Acropolis while you wait.
I have not used this persons services, so I cannont comment. I clicked the wrong business to review, please delete me.