We visited the South of this island in the autumn. The island itself is lovely. But I won’t be going back because of the wasps. Every time we sat anywhere for lunch we were swarmed. We had to always eat inside, which was a shame as the weather and food were great. I was even out swimming in the sea and some wasps came around me.
We didn’t have any problems with mosquitoes or cockroaches. So I guess it depends which bugs cause you the most worry.
Link to Sardinia on Wikipedia.
Maybe Sardinia is better at other times of the year? Maybe the North of the island is wasp free? If you have visited Sardinia then please add a comment to describe what bugs you encountered there.