The front ball diff gives you better cornering. I ran the solid front at first then upgraded to the ball front. I broke two outdrive cups and bent the front dogbones a couple of times with the solid. The front width has to be reduced to run the ball diff, or the dogbones pop out. The ball diff gives you a lot more tuning choices. It might take a while to get the front/rear balance right, I am still working on it. If it wasnt for the breakage, I would go back to the solid, it is a more simple setup.