I have the large bottles that I rent out at the shop and I also have one of the little suitcase sets at the shop. It's really handy for making a small cut and just being able to carry the torch right out to it. The oxygen doesn't last very long if you can''t try any serious cutting. I have the largest bottles I can buy at the house and a rather large torch. I would recommend this to anyone who works at home to go that route. I bought the tanks from Indiana Oxygen and I trade them for full ones at the local welding supply. I have 2 oxygen bottles because I usually use the torch after hours and o2 always seems to run out right before I'm done.