Rubber or aluminum alloy valve, which is better?

Rubber and aluminum alloy valve, which is better? By contrast, the rubber is one-piece molding, it seems that it is not easy to cause air leakage due to the valve itself. The aluminum alloy valve is the same length as the tr434 rubber valve, but the base is aluminum alloy. It needs to be sealed with a rubber ring, so there is a joint between the rubber ring and the aluminum alloy base. If the seal is not good, it may cause air leakage. Then I paid special attention to the observation. The vast majority of vehicles on the market use rubber valves, and so do new vehicles. There should be a reason. Maybe considering that the leakage point of the rubber valve is less and more reliable, the aluminum alloy valve may be replaced later.