I think the only reason for it in a street car is if you are determined to put a Ls1 in your Third Gen (I know Kevin-blasphemy) it saves the trouble of having to cut out and gusset a part of the stock k member for clearance.
i bought one and i'm just waiting to get it in the mail. The only reason is because i got in an accident and messed my stock one up. should look really nice. not sure if it helps the suspention at all. saves some weight though.