"I have found these cause trouble after a fairly short while, whereas Pegler valves can be left and forgotten. If you open them up, you can see where the corners have been cut. Admittedly, Pegler valves are about 6 times the cost, but I think if you have to use a gate valve, you might as well go for long term reliability. You sometimes see Pegler valves on ebay where plumbers are selling off surplus. I bought several at £7 each recently."