The key profiles [Rows labelled 1,1,2,3,4,4 from bottom to top] are the same and if you are mixing and matching Das and WASD, the height of the keycaps are also identical so you wont have any problems there either.
I had two Das's, one is now used by the gf and I sold the other one with its WASD keycaps on it so this comes from experience.
HTH