I have 35% tint all around and I think it is just borderline, almost too dark. But I'm not as much of a baller as the rest of you young whippersnappers.
If I could do it again, I'd still pick 35% over 50%... but I'd take 40% if FormulaONE offered it in their Pinnacle line. Thankfully, a light interior makes my tint look a little lighter. Dark interior makes 35% look very dark.