Does it work? Absolutely!
SUNLU FilaDryer S1 Works amazingly well, easy to use (2 bottons), can adjust temperature and drying time.
Lets the spool roll on bearings inside so it can print while still in the dryer for those long prints!
Get it now:
https://www.sunlu.com/products/sunlu-filament-dryer-s1-an-advanced-drying-box-fit-3d-filament-1