Coloured Leads

Has anyone had much success using coloured leads? If so, care to share what colours worked best?
Have seen some of the boat lads using these and wonder if they could work from the shore?

Have used them, but did not notice any real difference to be honest. some like them some dont. but they are easy to find in the dark

found the yellow ones to be very good for flounder? could just be me, twitching it really seemed to get positive bites