These nuts are light! Metolius achieves this by attaching the cable directly to the nut and eliminating the swage. The absence of swage also make them feel less bulky on your rack. They have anodized heads and their swages are color-coded to match Metolius cam colors, making selection of the right size easier. The two curved sides set the nut and keep it stable, making it less likely to pop out from rope drag. This feature made Curve Nuts among the best nuts for parallel sided cracks. The taper wasn't great; they worked just above average in flaring or pin scar placements. The double curve design also helps these Metolius nuts excel in more featured rock like that at Joshua Tree and Metolius's home crag of Smith Rocks.
The cable kinks over time, although not nearly as badly as on DMM Offsets or Wild Country Superlight Rocks. The cables are burlier than many others but have limited movement; after repeated aggressive cleaning (pulling up on the cable to get it out) the cable can start to bend and fray. Also, it is disappointing that Metolius makes no small sizes for this model. So it is close to being a complete set but falls one or two pieces short. Metolius does offer the Astro Nut, which is made of bronze, but like all non-aluminum nuts these are far less durable. The curve of the Metolius nuts that helps keep them from popping out also makes them harder to remove.
Metolius Curve Nuts and Wild Country Superlight Rocks are the lightest we tested. This makes Curve Nuts a great option for alpine climbers or anyone looking to save weight. Their three-point point curve is tapered nicely and works well in an assortment of placements and rock types, and excels in irregular rock.
These are among the more expensive nuts tested. But their light weight combined with an excellent mixture of placement options makes them a good buy. They are a worthwhile purchase for climbers who will pay for weight savings and above average performance and don't worry that Curve Nut cables need careful handling to keep from kinking.