I would rate it as this:
Seasonic > XFX/Corsair > Antec
but for Corsair and Antec, you have to be careful, since they don't produce their own PSUs, the Corsair enthusiast series is produced by Seasonic, so those are good, however the builders series is produced by some other company, which has worse reviews than the Enthusiast series PSUs. Same goes with Antec only I don't know who produces Antec's PSUs.
No way to answer ......advice about brands should be taken with a few pounds of salt . Which of the following do you think is true ?
Antec makes crappy PSU's
Antec makes good PSU's
Antec makes very good PSU's
Antec makes great PSU's
The answer .... all of the above. Manufacturer's are in business to make money ... the more they sell the more they make. Targeting a single market segment limits the number of customers you can sell to, limiting the amount of sales. So most vendors sell to multiple market segments: