I've never used the Crumpler strap, but I shot for a while today with my gripped D800 with a 24-70 2.8G lens attached (fairly hefty lens), and had no issues. It is definitely more comfortable than my BlackRapid was. There is a slip resistant zig zag of rubber type material on the inside of the strap that keeps it from slipping and sliding. Today was the first time I've really used it and it did everything I thought it would. Definitely one of the best accessory investments I've made.