I personally don't care about a company's overall rating, or how many 5-star ratings they have. I do read a lot of the 2-4 star reviews, however. I figure they're likely to be real reviews from employees who have mixed feelings and something worthwhile to say. I also check out the reviews on benefits. 5-stars is easy to fake but benefit data is usually accurate...the truth will come out pretty quick if it isn't.
I don't care about overall ratings for many reasons. Two relevant ones:
1) I don't know how many reviews are fake
2) I don't know how much a given employer encourages their employees to write reviews. Obviously a company that encourages their managers to write reviews will have a higher rating than one that doesn't.
Here's a related article about companies efforts (both legitimate and illegitimate) to boost their ratings: https://share.qz.com/news/1388923/body/
Before that face-to-face / phone interview happens, what do you do to get more information about a company you're applying for? What about once you are interviewing? Have any questions you ask every prospective employer?