They just seem to take small plates offensively mate, I don't run one because I think it's just a reason to pull me over.
I'm not being holier than thou, jus ttrying to limit on one thing I know they'll just nab you on. I've only been pulled over once in this country (my first ride with the Surrey crew and ended up on TV!!!) and I had no kite mark on my 54mm Sil Motor's and they weren't happy with my rear SuperCorsa (although there was nothing wrong with it!!) but nothing was said and thats it! But .... with 8-10 of us there, only 2 had legal exhausts and nothing was said but there were two producers for small plates. Nothing about tinted visors etc ... just the plates.
I'm leaving mine on ...