I have a Dritz 60mm that can be adjusted to light or heavy cuts and the shield is retractable. It is also equipped to be locked when not in use. I also have the Olfa 45mm and a smaller one yet just for trimming dog ears (on HSTs!), and I recently purchased an ergonomic Fiskars 45mm. I can't say which one I like best, as each has a quality or qualities I like.