Central diff any good and the diff spool by traxxas any good has anyone tried.??

I used to use one in the rear. Its lighter and stronger than the stock diff, but it pretty much destroyed my rear cornering traction on pavement. I just bought a second one, so Ill be testing it with spools at both ends. It should make for a fun handling car to slide around in the dirt with, but I wouldnt drive it on the street with a spool at all.