so far my best 1 to 1 exchange experience should be dealing with Jacker for the powerbank. 2 times some more for my 2 different colleague, his 1 to 1 exchange was not 7 days but 6 months . case 1 manage to get 1 to 1 after 5 months battery kong. pm him , tell him problem, no much question, he agree with the time/place and excahnge with me. that time i was 1st time deal with him. due to this experience, i recommend some of my colleague to him as well.

another case was test use after weeks cant charge. he jsut change for me, open the other set infront of me and put the new warranty sticker. everytime meet up less then 10 min settle. now i would say this is 1` to 1 exchange.