Image have been laughing about the discussions related to light leaks of A7/A7r by "internet pros" (people with brains or actual photograhy experience would never worry about this). People have been complaining that light leak is visible with ISO 25600 and 30s exposures. I have been shooting quite a lot with Hoya ND400x and B+W 1000x, and when sun is shining exposure time @ f/11 is close to 30s @ ISO 100. During my Crete holiday there were no photos with light leak issues.
On landscapes including sea I prefer to smooth the sea surface with strong ND-filter. Also when combined to sunshine from high angle and polarizer, this can also visualize coral reefs and other stuff close to shore (better visible on 2nd photo).
Carl Zeiss Sonnar 2.8/35 ZA @ f/11, 20s, ISO 100, B+W Kaesemann Circular Polarizer MRC 58mm and B+W 110 ND 3,0 - 10 BL 1000x E 67mm
Carl Zeiss Sonnar 2.8/35 ZA @ f/16, 75s, ISO 50, B+W Kaesemann Circular Polarizer MRC 58mm and B+W 110 ND 3,0 - 10 BL 1000x E 67mm