Phu Quoc is a bit of a strange place. Typical Vietnamese over development with huge resorts at either end of the island. Some really nice smaller places in between. Depends what you are after.
We stayed at Ocean Bay Resort & Spa Phu Quoc which was exceptional in our opinion although we aren't travel snobs and this was a real treat.
Ate at Restaurant Eat Pray Love Phu Quoc which was ran by a couple with a daughter and the food was excellent and cheap.
And Rory's beach bar is an institution and great for watching sport if anything is on. Great food as well.