I HAVE TO PUT THIS OUT THERE
We have an auto body chain called TASCO near here I use some. I have their cups. I noticed last week when doing my car that the cup is more narrow at the top and he scale on the cup is obviously off. a 1:1:1 is easy to see if a mistake.
I have used SPI products for 6-7 years and never an issue BUT I only do maybe 2 cars a year of my own. I am no a pro!