Avoid horseshoe curves. If there is “hack” this is it. Products with a lot of 5 reviews and a lot of 1 reviews generally indicate the real reviews are the 1’s and the fake reviews are the 5’s to pull up the score.
Look for reviews that look like a crescent with the longest part of the curve on 5 Rating and smallest on 1 rating. This is the sign of a good product with a typical review curve. Not everyone loves a product no matter how good it is so it is healthy and normal to see a progression of reviews from 5 to 1.
Read the reviews and comments. Take the time to read the good and the bad, and the comments. It is pretty clear when you are reading a real review and a professionally written review. Read comments on bad reviews because while the selling companies will feed good reviews for their products, competitors feed bad reviews and misinformation about their competitor’s products that cannot be removed by the manufacturer. See how the company responds to these bad reviews. It will tell you much about how much they care about their product and customers. If they let the poor reviews stand they clearly are not very customer driven. If they offer good explanations or offer support for the bad that is a great sign they are a company you want to buy from.