Which is better, Shen Yan Gas or Gas Group?

Do not use deep rock gas. It's dark. Last time, I added a can, which was unopened, with a total weight of 28. 1Kg. Later, I only used 17. 1Kg. Even if there is tail gas at the bottom of the bottle, it is 4Kg short. Their official website standard is that the gas label is14.5+-0.5kg. That is to say, with the bottle weight of 15Kg or so, the total weight of the whole tank of gas should be about 30Kg, and they are obviously missing two kilograms. For this reason, I also talked to their staff and said that the service attitude was too bad. Let's prevent being cheated.