What works for me is, the reviews should fall off like a neat stair case, 5s the most, then 4s, 3s, 2s and 1s. If the 1s are bigger than the 2s by a lot, it's

What works for me is, the reviews should fall off like a neat stair case, 5s the most, then 4s, 3s, 2s and 1s. If the 1s are bigger than the 2s by a lot, it's usually the classic "Sell 500 good quality ones, get the reviews, switch to the knock offs".