I have all LED's fitted to the back end of my trike and it's gone through the MOT no problem. I'm using two stage LED's so the same light gives side and brake, the brake being brighter than the side.
regulations for LED lights
Now with the new 1641 engine and a few more bits finished.
The LED's were imported from America and have two intensities. All the lamps light but on sort of half brightness, then full brightness. I even have two of them wired up as fog lights and nothings been said about that either.
regulations for LED lights