These slings wrap around the shoulder without digging or interfering with reach. Precision lamination and die-cut technology puts them in the same comfort field as high-end backpacking shoulder straps.
On a big wall and carrying a heavy rack all day I found the sling to be under padded. It also had a tendency to spin around such that the padded part would be hanging down while the narrow side, where the pro should normally be, would dig into my shoulder.
Next time I'll buy one with some gear loops built into it. Not good for much except a light rack on short climbs.