A friend of mine bought this rack and they are so handy and way cheaper than cams. I like them better than stoppers or nuts because when set right they cam. They seem to be a quality product that you would would expect from BD. I liked them so much I purchased a rack the next time they went on sale.
I never trusted these until I went on a trip with a friend who swore by them. Somehow he was able to place at least one in every climb he did over the four days we climbed together and finally I took my turn. Nothing else seemed to fit in this one large constriction spot and I didn't want to our of pride, but grabbed one of these hexes and boom! perfect fit. They are not as heavy as you would imagine and due to the polycentric design are able to fit in a HUGE array of spaces. When they fit, they fit...well enough to hold a tank for as far as I'm concerned. Plus...they make really cool clanking noises when they're on your harness and climbing!
Got this hexes some time ago and have been using them for new apertures, they fit just perfect for some cracks. The size and angles they have are really good to place them correctly on the rock, kinda like a bombproof protection. It won't come off easily.
"Good, but I don't see how these replace cams"
I bought the largest three sizes, but I don't see how these are supposed to replace cams. Maybe I'm a total NARB, but if the crack is parallel, how does the cam not fall through? However, these are great where a nut is not long enough to stick behind a protruding feature.
Finally got to use these after ordering them a month ago and must say, I like the options they give me. Between these, some stoppers, and a few tricams, I never placed a cam on my first 3 climbs leading on gear. There's something nice about finding that spot where both sides snug into the crack you know it's not going anywhere.
Every traditiona trad climbers should have one set of this hexes, are very useful when you want to have a light rack, this hexes can reduce the number of equipment you carry in your rack because of its three different widths, this means that carryng one Hexe is like carryng three different Chockstone sizes with you. The Hexes also are very usefull in sections where the crack opens wide where the cams can not feet in.