Being an interference engine means nothing in this instance. The intake valves are not being sprayed by the gas, and thus cannot be washed off by the additives in the gas.It's an interference engine yes? Then it will get to them. Won't happen instantly, but it will get to them.
You can run snake oil in your gas all day long with no deleterious effects, but you're not gonna convince me that it will magically clean your intake valves.