So you highlight the good experience you had with Zotac and ASUS, and ignore all the complaints that people file.
Every company has RMAs, and some individuals might be experience a spike in RMAs compared to others.
I've had one Zotac card failure(1/2 so 50% failure rate), and one ASUS card fail(1/2 again, so 50%). Based on those numbers, they must be unreliable! Except I don't think that's true. Sample size is too small, and I would argue that so is yours.