The purpose of a torsen diff is very similar to that of a limited slip diff, it transfers more power to the loaded wheels rather than dumping it all on the unloaded wheels like a regular diff will do.
This helps with acceleration as the front end of the vehicle unweighs shifting the weight to the rear wheels the torsen keeps the power going to the rear whereas a normal diff would start sending it to the front. If you've seen pictures of RC cars with tires that looks like pizza cutters then that is what happens with a normal diff. Now this is a benefit on hard packed, high traction tracks or surfaces. On loose tracks or surfaces it will cause too much grip and make the handling feel loose and bouncey also causing strong on power understeer.
Bottom line is that if you have one try it out and see if it suits you and where you use it. If not then experiment with your normal diff by trying different weight of diff fluids and see what effect you get.