how to tell if a whipping cream dispenser is overpressurized or underpressurized? The question is simple - how to tell if a whipping cream dispenser is overpressurized or underpressurized without the risk of removing the head?

Note: Initially I submitted two questions in another single post (where you can read the background for my question), but only one got a great answer.
There is no pressure gauge on these devices, nor is one available even on the professional line according to iSi's website. I don't think it is possible to determine the pressure inside