You've already searched for a product that has the features you want, so you’re probably already looking at the right things for you in the features and aesthetic department.
The negative reviews will tell me things like if the product or parts of it failed or broke. If it doesn’t do the job very well, lacks power, accuracy, etc. If a keyboard, is it loud? Fatiguing? Are the keys replaceable? Do they keycaps wear and become illegible? How “sloppy” are they? If it does fail, is there customer service? How many people get DOA items? How many bad reviews are for dumb things like color or buying the wrong product for the job?
So see what people disliked about the product you think looks shiny and pretty before buying.