My experience with wally world batteries is not stellar, but I could have treated them better too.
In 2007 I bought my last 3 at the same time.
One shorted a cell in 11 months
the Second developed high resistance in 22 months
The third lasted 7 years total after being delegated to engine starting duty only, and never cycled again. It was extremely weak at the end of those 7 years. 2 seconds of engine cranking OK, 3 Not.
To say a group 27 wally world battery is the same as a Trojan group27 or a Crown 27 is asinine, but then again so is thinking any group27 is a true deep cycle battery.