7mm is perfect to cover the hole, and not look like a glob stuck on the ear lobe. Very light weight.

My issue is with the back finding, it is too tiny and it does not want to go on or come off easily enough, so it is a struggle to put on and take off. I normally might try to adjust the tension of the finding but it is SO small I can barely hold it between 2 fingers, and can't see it when I am holding it in 2 fingers.