Note there are "benevolent dictators." Singapore, I would think.
Alright; and, in other circumstances, maybe that would be a valid case to make1 - but it's kind of beside the point. The truth is, Portugal isn't a "guided democracy"2, and Anibal Cavaco Silva wasn't a dictator: he was elected; performed his duties (I won't say well, but at least) within the bounds of his office; and, considering his term is ending, the next president was recently elected3 (Marcelo Rebelo de Sousa) and will take his place in a little over a month.
1 - although, it wasn't that long ago that Portugal got rid of its dictatorship (1974), so any such arguments are not likely to find a lot of sympathy with the natives.
2 - well, to the extent that most Western countries aren't, which is debatable, I admit, given the constraints of the European Union, and/or the overwhelming influences of countries like the United States and, to a lesser extent, Germany.
3 - in fact, I'm not sure if they have finished counting all the votes yet (although the outcome is clear): www.rtp.pt/noticias/eleicoes/presidenciais/2016.