The latest Amsoil magazine is announcing an upper cylinder lubricant. There is info and charts about how well it works.
It says to use with every tank. The cost would be about $2.00 for enough for a 12 gallon tank. That's close to 15¢ a gallon to add this to your gas tank.
But is the treatment really worth a extra 15¢ a gallon when Top Tier gas is only about 5¢ extra a gallon.