Not only do sizes vary between brands but they often vary between models within the same brand. Case in point: I have a pair of Lake mountain bike shoes in 43 wide. They fit perfectly. I changed to a set of Lake road shoes. The 43 wide was so short the first four toes on each foot was smashed into the toe box. Tried a 43.5 wide, a 44 wide, and finally went to a 45 wide before finding the right fit... for that shoe. Very strange.

Hope that helps.