I like how fast and easy it is, it just plugged into my phone and i kept it in for 15 minutes then i'm done! Way more convenient than having to keep the trays or strips or whatever on for hours just to get the same results
though i never heard of Shiro i decided to give it a try because of the price and was not disappointed. It feels like good quality and worked as good as any other teeth whitening I have tried plus didn't bother my teeth. It was pretty quick to see my teeth get whiter too which was surprising considering it's not long to wear it each day.