ok here is a question that is worth asking!!

The welded center diff is strong, i have heard of people breaking speed design diffs but never welded diffs( doesn't mean itr hasn't happened i just have never heard of it). you can also dyno with this set up. If you can pull the diff jerry does it for like a 100 or so. The problem with welding the diff is it is hard on your drive line(ie cv's, and u-joints) the reason it's hard on the drive line is that at slow speeds it tends to bind up esp. when backing up like in parking lots.

the welded vc makes the cars ture 4X4 liek the welded diff and enables you to dyno.An andvantage is that it can be removed fairly easy when not racing to give you back the low speed drivablity. the problem with it is that the diff is a big weak spot in the tranny and this does nothing to make that stronger.

hope this cgave some insite.