I'm open to any suggestions about installing an engineered wood floor on a slab. I would like a floor that isn't "too easy to scratch". Hence that's why I thought pecan or hickory. I will GLUE the floor down.

What is the difference between the pecan and hickory? Does it darken with age? Any other types of species I should consider? (Brazillian Cherry is too dark for our taste. )

Once the wood is made into lumber, you can't tell Pecan from Hickory.