I have it. Fitting it was much as the Tesla instructions but I think Tesla’s tool is slightly better designed.
They make a small whistle at speeds over about 50mph, not sure if the Tesla ones do too. If you’ve got any music on or if you’re having a conversation you won’t notice.
I think they look quite neat, I’ve just left them on after putting them on the first time. I’ll probably leave them there until winter when maximising range is more important.