Quick one for PSI expertsLooking at upgrading my current machine which is fairly basic to a much higher PSI machine......My question is, is 800 PSI necessary, it is adjustable so do people using these machines actually ever set it to such a high PSI?Hi matepsi is one thing - but a good vac is another - just looking to sort a storm myself - the airflex pro800 is cheaper with sim psi but the vac power is 6.6 like the jag - so for dryer carpet and better extraction, a powerful vac helps a lot. 400psi is only really for hard floor type cleaning, if im right in my thinking.