^ allow me to disagree. wood cups makes a lot of difference, now is up to the listener to decide if it is for good or bad. the grado sound is still there, but you can play with the ammounts of bass (most common) you can also improve clarity, how bright or dark you want the sound to be... etc etc.
In my case I have 3 grados with different housings and only in one case I regreted the changes (grado SR80, ended up with way too much bass). the others two, I love them.
for me the sound alone worth it. plus you gte to have a unique piece of art made by yourself.