Maybe?

I read a lot of posts here about how a voltage is low or high on a certain PSU, and then another person who gets fine voltage with the same brand PSU.

Do you think that the voltage may vary based on other factors besides brand? I was thinking somewhere along the lines of power line quality in the person's house. One of the things I learned in A+ class was that if you're having power problems, that it may not be the PSU to blame but the quality of power in your house. Some live in newer houses that pump electricity great, and some live in an older houses and your lines may be worn.

What do you think about this idea?

sounds reasonable. maybe that and how much you have hooked up on the same outlet? i'd guess that most ppl have way too much on the same line...especially in this crowd

I can maybe see it being a problem with really old wiring.