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I have 3 WD 1 TB drives of different lines (Blue, Green) running in 3 different PCs for over 3 years without a hiccup.

Sigh. When one of them fails, you'll have a failure rate of 33% and suddenly WD is terrible?

Statistics 101. The accuracy of an average is related to the square root of the number of observations that went into it. So Backblaze's observations of thousands of drives probably allow them to compare failure rates to about 1.3% (ie annual failure rate 4% means ina range ~ 2.7% to 5.3% range) and just about everyone else's set of data is too small to say anything much at all.

But in any case, the real devil is common-mode-correlated failures. You can almost always protect against randomly distributed rare failures by using mirrored pairs of drives. But if you deploy two drives with near-consecutive serial numbers, failure of the first from certain causes becomes a good predictor of the imminent failure of the second. So buy one from each of two manufacturers and pair them. Even if the second manufacturer's drives are reliably known to have a higher failure rate, using it makes it far less likely that you will suffer a two-drive failure and downtime or worse.

Oh, and do make sure that someone is monitoring the drives. Recently I heard about a NAS box that had been screaming "one of my drives is dead" at the e-mail address of an ex-employee for about two years ... yes, the other drive died defore anyone noticed. TbftgoGgI.