Originally Posted by BlackOmega
You both need to realize that an OEM, such as SeaSonic, makes the components to the other compaines specs, not theirs.
So while the re-brands or core component PSU's may share parts, they're not SeaSonics.
In most situations, there is not much involvement from the brand selling the power supply. Rarely it's a custom design both companies work on. Sometimes, the brand may work with the OEM for a few minor modifications (fan change, capacitor change, a couple filtering components removed here and there to cut costs, etc.). Of course, the cabling and housing are often changed by the brand putting in the order with the OEM.
Regardless, the circuit design is generally the same, so performance and reliability are generally about the same unless the modifications are pretty gross.
"Share parts" is really really understating the similarities. The key factor is the circuit design, overall topology, control ICs, etc. Assuming you're not replacing the Chemi-Cons with Fuhjyuus, you're getting pretty much the same electronics. If you look at the majority of Seasonic-OEM power supplies on the market under other brands, you will not see much change other than cabling, housing, fan, and fan control. Seasonic is not a low-cost OEM, so pretty much everybody using their services isn't intending to scrape the bottom of the barrel on BOM parts, so everything but like Antec Neo Eco keeps the Japanese capacitors, for example.