that likely comes down to 'different people are different'...photonic wrote: Very helpful again (you rock). So why then do some people post that this makes breathing more uncomfortable. Seems odd to me...
some people find 4cm of air to be stiffling, like they can't breath, some people like it fine, which is why most machines start there, (some even go down to 3cm).
some people find 10cm to be too hard to breath out against, while others don't have a problem with 20, or even 25cm.
lots of people start out feeling that they're working against the pressure of the machine and after a fairly short time can't really tell it's even on. (sometimes I wave my hand in front of the vent to make sure, the perils of a quiet machine, I guess )
so, why do some people just have to have xflex/epr and others don't like it.... ya got me