Asset backed currencies have been the ONLY succesful models tried. They stood for centuries, none ever "failed" they were all replaced by fiat systems.
The dollar was removed from gold backing in 1971, but it was weaned from gold onto oil and the "petrodollar" was formed, it was a brilliant plan and when put forth to Saudi "leaders" they realised that if they got in on the ground floor of the pyramid scheme they would greatly benefit.
Fiat moneys have ALWAYS failed. The ability to "print your way out of trouble" is in fact "printing your way into trouble" and will always end bad for the users (good for the bankers).