As a writer it's very important for me to advocate for the transparency of information and well-written sources of information.
It's no surprise that most people are searching for feedback before they eg. purchase or use a certain service. That's why it's so critical that the people who write them obey those laws.
It is essential that you compose your articles both insightfully and critically. Feed the audience with pure facts about the company / product / service you are describing. Characterize the object as a whole, then include some more detailed features, but all the details. You can share more subjective thoughts at the end of your post, but they should be more applicable to the topic of which product is appropriate for and potential advice. For instance, a good sample of article which covers both sides is this TransferWise review.
Don't forget to address the product or service's advantages and drawbacks and ensure that you have a clear picture of it and have ample reasons from both sides and express your opinions and to determine whether you should agree on the service.
Regardless of how nice the review is, sadly, less people would necessarily read it if it is too long. Therefore your article should be short, but cover all the basics at the same time. Make a table of contents so that the readers can find conveniently the items they are searching for more transparently. Try using verbless phrases, or even construct a diagram to explain the conclusions.
Seek to always be as accurate as you can and always endorse your claims from sources. Recall the official website link and only refer to verified information. Any screen shots or customer feedback may also be included in order to make your article look even more professional and accurate.
Tighter, facts of the matter will not have the same impact as that given to advertising by the product / service. Average viewer, who isn't the field specialist, can see but relate to all your points and numbers. But, when you construct a ranking or chart that contrasts the object with the other objects, that's something different. It indicates whether the product is good or bad as transparently as possible.