“I have a couple of pairs of Squad MTB XL, and have tried a few lenses.
I cannot stress enough - the Chromapop Contrast Rose Flash is the lens to have - it's amazing! Feels like a clear lens in the shade/trees, and feels like a tinted lens in the sun. I have tried the darker lenses but they are no good in the trees.
The bigger frame size of XL makes for a better viewing window, but be aware they wont fit inside some smaller helmets. They fit fine in my Smith Mainline.”