I dont know. Some guys have good luck with 10 bolts and if your running a A4 with a factory stall odds are your rear end is going to live 2-3 times longer then a T56 guys would with the same mods. Now if you plan on putting a big stall on it or hitting the bottle off the line then yeah i would just invest in a 12 bolt now. But if your running near stock i think you might get a little more life out of her then you think.

PS: If your going DR's go with MT.

 

Now on the other side of things i have seen this happen at the track. The guy had just rebuild the thing too with beefed up axles and gears. I asked him why he didnt just upgrade to a 12 bolt and he told me "i will when i brake this one" 10 mins latter he was packing his car up on the trailer after he broke an axle on the first pass.