Sure-grip

I have a Duster with the stock 318 (aftermarket headers, intake, and carb though) and I think it'd be nice to spin both tires when I want to lay down some rubber rather than just one. I was wondering if I should go with the Dana Power-Lok or the Borg Warner sure-grip/whether or not it is even necessary. The Duster is just a fun daily driver, but I like to put Mustangs in their place from time to time. I've been doing my research, but need opinions from those who have them.