I have slid/rolled a good 50 or 60 ft maybe more in Joe Rocket at a realatively slow speed (went down at about 35-45 mph), not a scratch where the jacket covered, bruising yes, road rash no. And I hate wearing a jacket on a really hot day when I see others with no jacket or sleeves but I almost always (98% of the time)wear the jacket and bite the bullet, drink lots of gater aide. I am on my second Joe Rocket and in the winter I always wear leather.
Sherri