I must be lucky, I've never had a coil whining PSU in about 14 years....I am anal about silent computers in general, especially fan noise so I can understand its pretty horrible if it happens to you. It would drive me nuts.
I dont think corsair are more prone to have it, corsair PSUs are more common than other brands and users are more likely to be enthusiasts who notice things like coil whine. Its weird the people that had a problem with coil whine, usually had it more than once on different PSUs. It certainly is a weird phenomenon.
Asus P8Z77-V Deluxe /Intel 3770K@4.4Ghz/ TRUE Cooler /Corsair Dom 2X4GB 1866Mhz /Intel 520 240GB SSD/ / Samsung 1TB F3 HD / MSI 680 Lightning /Corsair AX850 PSU/ Aurora 570 Case /Samsung S23A950D 120Hz Monitor/AudioEngine A2 Speakers/Osmium Aivia Mechanical Keyboard/Mionix Naos 5000 mouse/Pioneer Blu-Ray 206BK