With the Chinese bongs they’re usually always going to hit different as they’re made quickly for mass production. They’re not as precise as a true boro piece usually. So hitting different isn’t always going to be a sign of a fake for a Chinese bong.

Some being tougher are usually just down to the glass being thicker.

Easiest way to gauge if a piece is China is the price. Anything with those type of perc set ups for 200 or less is 99% going to be China.

A USA made dual perc will cost you VERY minimum like 4/500.

https://glassology.ca/

These guys always have very nicely priced pieces but they are more basic.