Chopper. I used a Vario Clipper when they were available, and now use a Shark made by Bearpaw. It is very similar to the Vario Clipper, perhaps even better. It cuts very precise edges and is consistent from feather to feather. One problem with it is that while it is good for many hundreds, perhaps thousands of chops, it does eventually wear out. Get the most use out of it by not hammering it any more or any harder than you have to. For the first few hundred chops, one moderate whack should do it. When you find that there is still unchopped feather after one whack, start whacking it twice. When you do get an occasional unchopped feather, carefully lay the top part back down without moving the feather. It will usually cut clean the second time.