I worked at Wal-Mart for 3 years and sold these batteries, but I honestly never paid much attention to them in regards to manufacturer, quality, etc. All I remember is that when someone brought one back for a warranty claim all I had to do was punch in the date of purchase from the receipt (or the month of manufacture if the customer didn't have their receipt) and the computer would spit out the claim amount towards a new battery. Free for 2 or 3 years depending on model, pro-rated for a couple more years.
Since I know that Wal-Mart is almost 100% reliable with this warranty I went there to purchase. It's about the only thing I know Wal-Mart is 100% good at.