Brightness in a turn signal is pretty important. Like on some motorcycles I own, the sun can reflect off of the large tail light covers, making the incandescent bulb almost impossible to see over the reflection.
A bright brake light and bright turn signals are supposed to be "annoying" or in other words, attention grabbing.
That's why I've been improving not only the brightness of these lights, but also the earlier actuation of the brake lights themselves as I describe
HERE.
Etarga's LED brake/signal lights are very good.
Cheers,
- Craig