sorry edited my post get confused there is no PowerXStream was thinking of ProXStream. the ProStream and ModStream are older models rebranded Topower. the GameXStream, ModXStream and StealthXStream are manufactured by Fortron.
various Antec, Corsair, PC Power & Cooling models are built by Seasonic. I think Antec is the worst in Quality when I say worst I mean in Seasonic terms not Power Supply, Antec Models are affordable so they don't request any high quality components. Corsair request the highest quality components even more so than Seasonic's own brand (see below) a while ago I replied in a thread on a budget build I think on what a Corsair 450VX can do, it literally has components from Power Supplies in the $200-300 range in a $60-80 Power Supply I quoted signatures (builds) from alot of forums of a 450VX powering a Quad Core, 9800GTX you name it basically any system that would make you recommend a standard Power Supply in the 500-750W range.
the Corsair 450VX is based off the Seasonic S12 II series what's the difference? higher quality capacitors, more heatsinks, etc.