The JWs take pride in their honesty, For many years, this has been a strong marketing strategy for the purity of their religious dogma. You may be familiar with many stories of their members retruning found wallet and so on, But here is an example found from the 2010 Watchtower, March 15.
"Emilio, an Italian Witness who works as a driver for a public transport company, found a wallet containing 470 euros ($680, U.S.). To the surprise of his colleagues, he handed the wallet to his supervisor, who later gave the wallet to the person who had lost it. Some of Emilio’s colleagues were so impressed by his conduct that they became interested in the Bible and started to study. As a result, seven people from two families have accepted the truth. Yes, behaving honestly from a pure heart really can move others to praise God.—Titus 2:10."
Do you think this experience is universal in all JWs cases?, and does it justify the trustworthiness of the JWs as a whole.