I use regularly for uptaking a variety of annoying weeds in hard-packed and sandy soils.  After you get the hang of holding this thing at the right angle, it cleanly slices through the stem and the 360 degree "looped" form of the blade lets you kind of flip the plant right into a bin or wheelbarrow without every touching the plant in most cases.  That is a real plus where I live as most desert weedy plants are stickery, spiny or otherwise difficult to handle.  I never knew this tool existed until I found an ancient version of it in the back corner of my garage, having been left by the previous tenant, apparently.  I've not yet had to re-sharpen the blade or anything but I think it would be do-able if it ever becomes necessary.