After a little bit more hunting, I found a more thorough description. One that verifies what you said, Main Stream.

""What is a RIPGRIP? It's the infamous limit slip insert thingy for your transmission's open-style front differential, designed to provide increased traction to both front wheels. We now stock them for the Mitsubishi FWD &AWD vehicles. Custom units available upon request. Q: Will it break? A: No, the RIPGRIP will not break. Q: Will it make my front differential spider gearset fail quicker? A: It's a possibility but you should understand that the spider gearset and cross shaft should be inspected for signs of fatigue or abnormal wear and replaced if necessary. Another important procedure while installing the RIPGRIP is to reshim the spider gearset to bring eliminate backlash. This is what we do to while rebuilding our transmissions and so should you.""

I found that at the very bottom of this page:
http://www.teamrip.com/news.html