The Op-tech Pro Loop strap is made from a stretchy neoprene material which will help with cushioning the weight of the camera and lens. The Crumpler Industry Disgrace is very well-padded but does not stretch at all. I think both are equally good if you wear your camera around your neck, and you should consider if you like your camera strap to be stretchy or not. Some people feel that the bouncing camera adds to the perceived weight, rather than reducing it.
The Op-tech Pro Loop has a grid of sticky dots on the underside to help it stay on your shoulder, but the Crumpler Industry Disgrace only has a "Crumpler" wording on the underside which isn't sticky at all, so the strap is definitely not recommended for shoulder carry. But if you like to wear your strap across your body, the Crumpler's length is very adjustable and the material makes it easy to slide along as you bring the camera up.
For shoulder carry, I really prefer the Op-tech Super Classic strap since its underside is a strip of sticky textured rubber. Others prefer Domke and Think Tank straps, which are lower profile and less bulky. I use the Op-tech Pro Loop attachment system so I use a Pro Loop and a Super Classic together. The Pro Loop goes around the more frequently accessed camera while the Super Classic goes on the other one that I want to stay on my shoulder till I need it.