I'm currently cleaning my fully pumped heating system as good practice. In preparation for flushing and adding inhibitor I note that Screwfix sell at least 3. The main two are Fernox F1 and Sentinal X100 but there is also Flomasta 0616 which is half the price of the other two. On a 12 rad system I can save £15 by using the Flomasta 0616. I'm more than happy to pay the extra £15 if I am getting something better but equally don't want to waste £15 for absolutely no benefit. Should I go for either of the main 2 or save my pennies?