How many of those user perspectives are real? It seems to be if you are a manufacturer of a certain product that it wouldn't take too much effort to promote your product with a few sock puppets in a subreddit until your product is on the subreddit's shortlist of recommended products. From that point on new users to the community will evangelise your product for you and you can scale back your sockpuppets.
If you manage to get your sockpuppets to be admin of the subreddit it's also not too hard to delete negative comments or reviews about your products or to generally steer the discussion in the direction you want it to take.
I don't trust reddit product reviews anymore than a top 10 SEO site on google with top 10 best <product>.