The best ferro rod is the one you will actually carry all the time so you have it when you need it. Pretty much all of these on your list I wont just throw in my pocket and let it bump around all day, day in and day out (except for maybe a couple of the smallest ones). I do however carry a Swiss Army Knife with me all the time and use it for everything. Tortoise Gear makes a ferro rod that fits in your Swiss Army Knife called the Firefly! The Firefly is hands down the “best” ferro rod I know of because I literally carry it everywhere I go and it takes up ZERO extra room in my pocket. The ferro material is non-chinese super high quality, low corrosion, high strength and easier to spark that any other firesteel on the market.