I find that the reviews can be of use, but you have to actually read them to get a feel for whether you'd like something or not. It's usually pretty easy to tell an honest review from a dissatisfied consumer from one created out of spite; the former will almost always be more detailed and specific about what they didn't like.

If there are a lot of reviews independently created that tell the same flaw too, then that could be something to seriously consider. There's a pizza place I haven't been to for over a decade, which is still around so I looked it up on Yelp. Turns out about one-third of the reviews complain about the bad attitude of the employees, but the reviewers were all over the place in how much to deduct from there, ranging from dropping it to 1 star to keeping it at 5 stars, indicating it's a problem they don't really mind. For that reason, I think that issue is genuine; I was going to visit it again soon to see for myself.