At the moment I am using a small electric coffee/spice grinder which I have just found on Amazon for £13.50, it has been used for maybe a year and a half with no issues. I also use secateurs to do the heavy work first, I normally get the pieces down to 0.5–1cm sort of size. Only thing I suppose some would not appreciate so much about the model I went for is that it doesn’t hold much, but I don’t have any issues with it personally.