[Goat Blower]

I don't see the attraction, they're almost the same price as Shep, who is the undisputed kings of DSM trannies. The four spider option converts the normal two spider center diff into four, spreading the force among more gears, which cuts back on the force each has to endure in a high torque application while still allowing the viscous coupler to do it's job. Which is allowing the front and rear wheels to turn at different speeds so you can go around corners without the tires skipping, not pleasant in street-driven cars. Welding the VC or the center diff is better for drag cars but doesn't allow the front and rear wheels to turn at different speeds which is very noticeable in parking lots and short corners. Welding the diff is much better of the two for less wear and tear on the tranny and xfer case if you're going that route.