Picking by "brand" s about as useful as buying by retailer. Might as well say get a good PSU from Amazon. Like retailers, "brands" buy their PSUs from someone else....OEMs. In seeking to maximize sales, they buy different units in various quality / price tiers to hit each market niche. Even among the OEMs, quality varies widely as each OEM has designs of varying quality called "platforms". So if looking for a PSU, neither retailer, brand name or even OEM name is a guarantee of quality. And while PSUs mane for different brands may be from the same platform, there still may be minor differences between them.
Does Corsair make great PSUs ?
Does Corsair make good PSUs ?
Does Corsair make mediocre PSUs ?
Does Corsair make crappy PSUs ?
The answer to all of the above is no, they don't **make** a single PSU. hage the word "make" to "sell" and the answer to all of the above is yes, they sell PSUs in each of those categories.