This is a problem the religion is going to have to face. It is the same with any product that one might find.
For instance, I have checked reviews on numerous products that I have bought. Some were trashing the product--I have checked reviews for Giant Rincon bicycles, and some have stated that the tires wore out after only a few miles, parts came loose or busted after a week of normal use, or that the bicycle was a piece of crap. Other reviews of the same product state that it was an excellent value (my own experience is that, for a $400 bicycle, that it is about what I expect. It is not great--the front suspension was too loose, the seat post was 100 cm too short, and the disc brakes slightly rubbed). But the bicycle has done a respectable job during its first year, with no signs of major problems. But, some will see those trash reviews and look for another bicycle (until they see the trash reviews that one got, too).
Another product that I have seen trashed online was Insignia TVs. The complaints are that the sound goes dead, or that the set goes off, after only a few months (and that Best Buy, which sells the sets, doesn't stand behind the warranties). I got one before reading those reviews, but mine has had no serious problems (though it is still too new to find out whether any will develop). It could also be that these TVs are unusually sensitive to power surges, since there are other reviewers that have had their Insignia sets working perfectly for several years. You are going to find bad reviews--I have even found bad review comments on Panasonic products, and even L.L.Beans products (even those where most of the comments were positive).
What is going to make things miserable for the witlesses is that virtually all the comments that make sense are negative. Unlike the products mentioned above, it isn't just a few people that have had very bad experiences with the products. Most people have had very bad experiences, and the ones that give positive reviews don't seem to have any substances aside stock arguments. And most of the negative reviews were not one particular weakness (the control chip on the TVs, for instance)--it is the whole religion that sucks.
Even more important, with a Giant Rincon bicycle, if you get a bad one, nothing stops you from getting a GT, Specialized, or Schwinn next time. If your Insignia TV conks out 4 months after you buy it, next time you can get a Sony or Panasonic. (Incidentally, Toshiba makes Insignia products.) But, if you join the Jehovah's Witlesses and they turn out to have major problems, it is much harder to drop out. Getting a bad TV or bicycle only wastes the money you spend on it--getting a bad religion can lead to continual hounding, a ruined life and lost opportunity, and possibly even being physically or emotionally dragged back into it even after it did not work for you.