Hmm, the torsen ofna diff is billed to have a 5:1 bias ratio. Any reason why it will not help with ballooning? It can't send all the power to the rear, but it can get more that a silicone filled diff will... Should help with braking too.
The xray diff design is not as good as the torsen IMO. I may give one a try as I have a dozen vehicles that I could use it in...