I read all types of review, watched many videos, people testing this cooler side by side of much more expensive coolers. I wanted to buy one that was Made in the USA. Many high-end coolers are not Made in the USA. USA made along with price I had to buy this one. I bought my new Lifetime 55 cooler July 4th for under $100. 
Without precooling it, I put a 20lb bag of ice in, took it home then filled it with about 20lbs of all sorts of food. I left cooler out for 3 days, in direct sunlight. Temperatures reached as high as 92 and low as 72 overnight. Opening and closing it several times, the third day less than 1/3 the ice had melted. I will test it again when I have more time to conduct 7-day test it states it will do. However, after my 3-day test I feel confident it will stand the test.
Finally, I will say, I am very impressed with quality and performance and recommend this cooler!!