EU is no state, they have no say in my way of diving.
And becouse we used 300 Bar tanks since forever there are no way new regulations to outlaw them, without any sound reason, would ever be accepted from the different nations.
Poseidon reccomend 8.5 to 9 bar, i usualy have all my first stages tuned to 9 bar, and it works well with both my jetstreams and the apex or aqualung i sometimes use. i have no strong cracking pressure or violent purge.
9 bar is just a notch over 130 psi.
Thats true only for Poseidon Cyklon. Everything else use approximatly the same IP as most others. And the Poseidon first stages that are manufactured the last 40 years or so are made to be used with a IP in the same range as most others.
So the only thing you have to have in mind with Poseidon...
What is commonly called "the Nobel prize in economics" is not a prize instigated by Alfred Nobel, it is instigated by Sverige riksbank (National bank of Sweden) in memorial of Alfred Nobel, and are therefore not a Nobel prize.