I ordered this helmet after trashing a Giro Prolite in a crit crash earlier this year. I initially was miffed at the weight, but it didn't end up bothering me. The helmet performed fine through the season until "the incident"... During a large road race, my front wheel was taken out by another rider at 29 mph. I went over the handlebars and down on my head, skidded for a while, then was run over by the pack. Destroyed my frame, shifters, jersey, bibs, gloves, and helmet. I walked away with just road rash.
I attribute the protection of my head to the beefier design and tough shell of the this helmet. It held everything together even though all the internal foam was cracked through. While I am sure that other lighter helmets provide great protection, I'm picking up another Mavic SLR because I know it works great.
After all that praise, I do have to ding it on one point. You can only store your glasses in the front of the helmet due to the vent design.