I will not shop at Walmart so I cannot speak to their product BUT used the Loves and the O’Reilly Auto Parts brands that are much cheaper no issues so far.
WalMart is a large company and always demands lower prices from the companies they deal with due to their large volume sales. But it is also known that due to these demands companies who don't want to lose the volume of business they get from this company many will cut costs through reformulation and/or dilute their products so they don't lose money selling to such a large mover of goods. Walmart only cares about its bottom line and looks the other way to make more money.
2003 Silverado Fass 165, 45% over injectors, Banks big head, Banks 6 gun, Banks Exhaust and filter. Bed Carpet, Pace Edwards electric Tonneau Cover. 122000 miles