I've heard of certain kinds of gas cylinders that are dangerous to use due to their incorrect design. In lieu of this, whoever or whatever company that manufactured such only did so just to make money & didn't think of the safety issues. Some referred to such gas cylinders as half baked cylinders.

The question here is how does one identify the so-called half baked cylinders?

Another claim is that some other gas cylinders are produced in a way that makes the gas easily exhausted.

How does a person know these type on seeing it?

Please your explanations are needed with pictures. Current price of gas cylinders is also allowed. Please.

Additionally, which pays & saves more between kerosene stove and gas cooker?