its really not about which one willhold power....Zthe quaife has a 2:1 ration and the torsen comes in either 2:1 or 3:1 ratio.
Must people i have talked to pefer the torsen for drag racing...altough DemonSVT preferes it for just about anything! lol

As for me i am happy with my quaife, as it has servered me well in 3 autocross events in the last 2 years...it may come down to price for you, as the torsen is usually slightly cheaper.
Lupe