Every manufacturer has defective boards.
Basing a purchasing decision on Newegg reviews is foolhardy. Some people will write a review for every product they purchase. Some people will only write a review if their dissatisfied. Some people never write a review. Some people will review a product they don't even own. And from my observations a large number of complaints could be avoided if the purchaser knew what they were doing, even though they always claim to have high technical experience.
The best place to actually see all the various problems is through the Manufacturers Forum. What I find disturbing is that Gigabyte USA does not have a forum. You can only file a support request because they must not want their actual defect rate to be known. Gigabyte UK does have a forum and I see plenty of users having various issues there.
Official GIGABYTE Forum - Index
Gigabyte also has a terrible warranty/rma policy
Gigabyte is extremely deceptive in my opinion, all manufacturers have defective items that slip past quality control, at least Asus and most of the other manufacturers are up front about it.