Justine won more majors and actually is a GOAT candidate on a surface (clay). during her peak years in 06 and 07 she was very hard to beat. Hingis won 2 majors less but had a lot more weeks at 1 and the same number of total tournaments won. Hingis also flamed out very early while henin peaked in her mid 20s. I have henin ahead comfortably. her peak suffered a little because it fell in the same time with some good years of serena who she could only dominate outside clay in 07 when serena was not really fit but on the other hand she was able to dominate serena on clay. 4 of her 6 wins against serena came on clay for a 4-1 record on clay including 2 FO wins which probably not many can say. unlike that hingis was not really a GOAT candidate on any surface.