To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzes reviews to verify trustworthiness.
Worked well for a few months and then one day there was a puddle under it. At first I thought it was a condensation puddle, but no, the freeze/gel substance between the inner and outer walls of the mug was seeping out through a crack which rendered it garbage. If you don't mind buying a new one every 6 to 9 months, it's a good freezer mug, but it has a definite lifespan.