I have always preferred Fleck metered heads on softeners. It is a much more efficient way to control salt usage than timer heads. The only thing I would like to see on Fleck heads is a better way to set the salt dose per regeneration. The tiny cam is too small to move acurately and the indicator is a guess to what it's pointing at. However, with a little trial and error you can find the right setting to make sure you run at 65-80% of the softener capacity which is the best salt savings.
This vendor responded very quickly and I received the item faster than expected.