The ones I bought from Cox & Buckles in England in 1988 have been on my 1958 TR3A since I completed the restoration in 1990. They were a poor fit (not a bad fit) but they still needed a lot of filing, trimming etc. Because they are soft, I took then to have then chromed. Then they buffed the surface and for the last 22 summers they look just like aluminium. The chrome resists pits and dings better than the bare anodized aluminium surface. But they have a lot of small picks and dings (probably by flying sand) and so I asked for a quote to have them reworked (recurved smoothly) and re-chromed. He wanted something like $300.00 for the two large stone guards. So I put them back on.
I have a spare set where the fit is so bad that I'm dicouraged just to look at them.
So I have been thinking, if you get small pits in your paintwork, you sand it and re-spray it.
So now I'm planning to remove the good ones which have been on the TR for 22 years, apply a very thin coating of body putty to fill the pits, followed by sanding, re-spray them with alumimium colour paint and hand buff the outer surface. They should look great again for several more years.