It is indeed proven its value. Though its rate is unpredictable, it is fair enough to people whose working on it. It is like a precious reward to every people who wark very hard in exchange of their service and loyalty. It might not be recognized by different countries and government nowadays because they were bounded by rules and regulations on fiat. However, it helps a lot of people to earn decently. I am looking forward that it will be used in the market like we used to do everyday and can be used as a paymemt for sustaining our daily needs.