There's been a load of duff Amperas as part of the Plymouth replacement scheme. Some failcompletely off while others are just glowing very slightly! There are also others which appear to have drivers programmed incorrectly and run dimmer than they should. What these LED lanterns do bring to the industry is an almost infinitely variety of wattages and driver current ratings. How on earth this will pan out in the long run when it comes to repairs is anyone's guess. No doubt replacing the whole lantern will be the norm!Well, bearing in mind how many ZX1s and ZX3s with Harvard electronic ballasts appeared in the scrap bins at the former local lighting depot before the PFI, complete lantern replacement will most likely be the norm. Even quick release gear trays didn't save these modern SON lanterns. Of greater concern is the replacements specified. This is not so much of a problem where a council specifies only a couple of differently specified variants for the whole city, but where lighting has been fine tuned you can guarantee they will just pull whatever is on the shelf off the shelf, rather than replacing like for like. For example, there is a motorway lantern swap scheme just about to happen near me. Where there used to be three variants of lighting (single optic ZX4, twin optic ZX4, 600W Sapphire 3) there will now be 13 different variants of Luma 3, with different lumen packages and optical arrangements.