Grant Kateswrote a review of Therm-ic Refresher USB Boot Heater on January 29, 2018
Familiarity: I've put it through the wringer
I love this boot heater. The timer is definitely worth the extra small amount of cash. That way you can set it and forget it.
As a daily user of my ski boots, it is important that I dry them out completely for each new day.