Not a replacement for standard open and/or box end wrenches...

Straight forward, they work. If you have easy access to the nut or bolt that you are trying to tighten/loosen they work really well and are comfortable to use.^M
But if you are working on anything that is a bit tricky to get access to (such as anything to do with exhaust systems or anything under the hood of a car) these fall way short.^M
You need a lot more horizontal (or vertical) movement with these then your standard wrenches. And there are just some things that you can't get a box end wrench on (this is how this tool works, very similar to a box end wrench).^M
^M
All in all they work, but not as well as they would like you to think.

Versatile within limits

Like other designs of fits-all wrenches that I've used over the years, this one fits a range of common sizes but it's too bulky to fit in a lot of applications. When there's enough access this and the fits-all socket made by Channellock can be handy substitutes for a heavy set of standard box-end wrenches and standard sockets. Like the Channellock design that seems to have been inspired by the design of a standard three-jaw drill chuck, this tool also seems to have been adapted from another very old type of tool: a ferrule crimper.