I agree with Muscle. The IRS is really nice to have for control and ride quality. Wanna drag, just add some stiff bushings, diff cover, and a few braces. However, the 96-98 cobra blocks are extremely strong ones though. What are your plans??? If you're going to build a 600+ street car, buy the cheaper one cause you will need the extra money. I'd go with the SN-95 on looks. Love the new edge, but just very fond of the 96-98 style.