I have quite a few friends who have done it, so I am interested to see what they have had to face. Many of them have had quite a few hair-raising experiences, but few have returned. A friend moved to the Algarve a couple of months ago - and his bottle gas supplier went out of business last month! The neighbours still aren't talking to them, so in the meantime, they have been to an animal rescue centre and acquired some puppies for company and to get them out of the house.
It's not for me, but the reason they did it was because houses are so much cheaper there that they have released a large amount of equity from their old house, so can afford to retire while in their mid-sixties. I think they must be settling in now though, I haven't heard from them as frequently for the past couple of weeks.
I would hate to live where they are, though. It looks far too hot already. I would miss the grass and trees.