I very rarely leave comments on videos I watch, but I had to for your video! Superb detail, great tests, links and to have written document to support your findings is gold standard.
Another excellent review. I have the Ugreen and the Ring RTC 4000. I carry the Ring in the car and have the Ugreen at home. I find the Ugreen more pleasant to use after about a month it discharged and it took several hours to fully recharge. The Ring has pass through. Again thank you for a helpful review.