Very good review Mike & John
I personally don't like the 13 mm. ER is tight and field curvature is a lot in a small Ep. I reackon imo the pentax is a lot better. But as Geoff said its all in what people like personally. The 14 mm UWA is a super Ep but its heavy, its only down fall.
Look foward to your 7 mm shoot out. The 7 mm Otho will win