Hi
Choosing a color should always be a personal choice. In this instance (i believe) you have chosen a rich reddish brown color for the cabinets (which I personally love) and are looking for the same color in the Santos Mahogany for the flooring. Santos mahogany is a very hard dense and very stable wood specie that would work very well in Kitchens that are going to be high trafficked.
The rule of thumb in my view is that you either somewhat match the color of the cabinets or go the opposite like a very light Maple shown here
http://www.hoskinghardwood.com/...ple-Natural.aspx?pId=795 which will create a distinct contrast between the cabinets and the flooring.
Not sure what the wood species you are going with for the cabinets but the Birch or Cherry will have very close grain patterns to the Maple too.
Either way the flooring will be beautiful, Good Luck
Jeff Hosking