I've posted this before in the Landscape thread but thought it might had to the 50/1.4 one as it fitted the bill perfectly when shooting straight into the light.
A six frame panoramic taken with 5DII + 50/1.4 @f11 1/10th, ISO 100. Each frame is the same single exposure, no bracketing, just exposed to lose the very highest highlights, working to the strengths of the Canon chip. Even in this situation 11.5 stops of DR is plenty. Another 2 wouldn't have held the sun.