I have one in an Ford 8.8 axle that is installed in my Jeep Cherokee. Its been in there for close to 15 years and 50-60,000 miles. I really can't say anything bad about it. It has seen lots of abuse, poor fluid maintenance(lots of water in diff) and has done great. It has slipped before but it was in circumstances where it was totally abused. Pulling a dead jeep, lots of rocks, big tires, heavy throttle lol.

As far as race car stuff a friend of mine had one in a stick shift mustang that ran 10.30s and didn't have any trouble with it.