So as i can see GOLD is backed by physical gold, which is purchased every time a token is issued and stored in a secure vault in Singapore. It is convenient and safety if it's work exactly as it said. People put money in GOLD and can be sure about finances.
You can always check the total available physical gold that is owned by GOLD project on bullionstar.com. The post I quoted give you details to check it if you want. It is not difficult to check it.