In my tests, where I filled each cooler with 3 pounds of ice and tracked the ambient temperature inside for 48 hours, the cheap Igloo was just as underwhelming as the cheap Rubbermaid.
The Igloo did manage to pull the temperature down by a few extra degrees, though, which makes recommending the Rubbermaid even less conceivable.
The kicker is that white line on the graph below, which tracks the cooling power of a disposable Lifoam cooler made from Styrofoam that only set me back a few bucks.
It was only able to pull the internal temperature from 70 degrees down to 58.4 degrees, which was a few degrees hotter than the Rubbermaid or the Igloo and hotter than any other cooler I tested -- but it also held steady at that minimum for longer than either one of them, and, tellingly, finished the test with a lower average overall temperature for the duration of the test.
In other words, the data suggests that your beers will get warmer faster in the Rubbermaid Ice Chest than they would in the Lifoam. I know.
Of course, your best bet is to set your sights a little higher and spend $45 on the excellent, my top-rated cooler to date. It's a few quarts smaller than the Rubbermaid, but the design has a drain and a lid latch, and it's much, much better at keeping things cold.
- Want more info on coolers? Check out our full roundup post for more tips and buying advice.