Do you mean aluminum dogbones?
http://www.teamyokomo.com/jpn/partsl...d_010440a.html
I have been using them for awhile now, and they have not shown any signs of wear. But, I do take them out every weekend and spray them down with motor spray. Then put two drops of MM Joint Lube on each one. This is a nice thick oil that sticks to the universals real good. Maintenance is key to low wear. If you maintain your stuff very good, then you should get them. If not, stick with steel ones. I think Yokomo did a good job selling them built in pairs (steel).
If you are wondering about weight savings, here is a pic....
