Mason mags cheap

I just ordered John Mason 10 rd. blue mags from USA Midway for $9.04 ea. They have 21 left ( I assume, they had 24 when I placed my order). They only have the blue in stock. Are these really good mags???? I have been looking around and they seem to have pretty good reviews. The PMI are hard to find and going for $$$$$. Has anyone had a bad time with the Mason mags? Your input would be great!