Received this set last night and started using it straight away. I experimented with a 1/4" radius first and had no problems, it made clean cuts and was generally happy with it. I then set up the largest of the set, a 3/8" radius, to use around some wood loops I had a solid 3/4" x 6" x 12" piece of yellow pine for my test, so I walked about 4 feet on the surface of the chisel before noticing yellow discoloration on the inside edge of the wood. (Where the stem and hinged flap meet. That in itself isn't a problem, but I've noticed that the yellow coating on the bits has already started to peel off. I'm not sure if this will affect their usefulness, but I have expected to last a little longer before problems arise, especially with such softwoods, only more time will tell how they fare in the long run.