It depends what the user is looking for, and what possibilities the machine will exercise in the future, and how the machine will be used, and if the user wants to be at the peak efficiency part of the curve, how efficient the user wants the PSU to be (Platinum, Gold, Silver, Bronze or 80+) and what quality of ripple suppression is in the user's interest.
Multiple GPUs now or in the future?
Gaming ONLY or multi purpose?
Gaming efficient or idle watt efficiency or the best of both?
What % of efficiency are they looking for?
A junk PSU used in an overclocked machine or a good PSU used in an overclocked machine?
and there is an order to making these decisions.
I am sorry but you are trying to act like you know something when you know very little.
Regardless what you said above......
Say your system uses only 400 watts max.....
Both PSU`s made by same company.
yet you want to get the latest greatest 800 watt Seasonic PSU.
When you check the price of the 400 watt vs the 800 watt you find that for $20 more dollars you can get the 800 watt unit.
Now explain how any of the above would keep you from buying the 800 watt unit...excluding price...even though $20 is miniscue.
You say efficiency....as if every Tom dick and harry are looking at efficiency. Let me clue you in...the average user is NOT looking at efficiency.
People need deal with the fact that just because a system might only use at a max 400 watts, there is nothing wrong with purchasing that 800 watt behemoth!!