But I find them useful and a lot of taps now come with flexies rather than hard piped.
The important things to remember are.
Don't kink the connector when installing. It will create a weak point and disrupt the flow to the tap.
Don't allow the connector to twist. It will stress it and potentially lead to failure.
Don't fasten them directly onto isolating valves. The rubber on the connector can be cut on the chamfer of the isolation valve. Fasten a spare radiator tail into the isolation valve first. This gives a flat surface for the connector to seal too.
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