We went to Thassos in May last year.We stayed in Thassos town but hired a car and went to Potos.It's a small resort and seemed reasonably quiet.The main coast road that goes all the way round the island does go through Potos but it didn't seem to be a problem as there were lots of small streets running down to the beach with cafes and shops etc.The beach is sand/shingle and tends to disappear from under your feet as you go in the water.There is a lovely church on the main road that regularly has weddings which are interesting to watch.Most of the bars on the beach tend to have sun beds which are free if you buy drinks from them.Also try Scala Potamias.Another nice small resort with a lovely beach and a nice relaxed atmosphere.