Regarding "phase inversion button"...
In short, if you do not have this magic button, do not despair. You are not missing much.
"Um, no one has it because almost no one finds any value in it."I have it. Two of them. I find it valuable to have them, at least I can say I checked for differences. At the same time, I find difference so minor that it seems to border imagination rather than real result.
In short, if you do not have this magic button, do not despair. You are not missing much.

