Hi Battista,
Have used PEC once or twice, but mainly ordinary e-mail if any. PEC is supposed to be, I think, like sending a registered letter. Makes little differance as I don't always get a reply anyway. As a matter of general interrest. I do follow up e-mails if after time I don't get a reply, but sometimes they never reply and there are people on this posting who must think I am not interested in their postings because they don't get a reply. Its quite the opposite. Its notorious here trying to get info sometimes.
Steve