Julian Hirsch was called "The man that never met a product he didn't like"
Look at car rags, they get a car, drive it around for a bit and rave about something or other and get advertising. Never mind they don't drive them for very long, they don't pay to get them maintained (and generally never talk about cost of ownership) they just drive them around for fun and that is their view. The more the car costs, the more they like it.
The same is true in audio--the more it costs, the wilder it looks in design and the more hyped the brand--the more they like it. Look at the mags and notice who advertises in them, you honestly think they would put out a bad review from their largest advertisers?
Consumer Reports did a review on a Bose 901 in the late 70's, they didn't like it much. Bose sued them, kept losing the case and finally lost the case at the Supreme Court. Sure, CR won but the rest of the audio rag industry would never say anything bad about Bose or even measure their speakers because they were afraid of getting sued. Bose also advertised more than any other company so if you said anything bad, they would pull all their advertising and sue you--so the rags had a hands off thing with them.
Most people that purchase things will tend to give glowing reviews, part of human nature. It is not very common to see an owner stating "I can't believe I was suckered into buying such a POS, I feel like a fool" Not going to happen, denial is the first phase and some people will claim to be happy even when they are not. This would explain why special speaker wires, power cords, cable elevators, audiophile spray for your CDs, brilliant pebbles etc. exist--because some people refuse to change their mind or evaluate it VS other stuff they own. The first one is always the best one.
If the reviews are on Amazon, I look at the negative reviews first. That way I understand what the negatives are or at least evaluate if the negative reviewer is clueless. If the speaker or product has some negatives that I don't care about or the positives far out weigh the negatives then it goes into the mix.
There are sites on the net that take the product apart, look at the parts inside, measure what they do and post pictures of the internal construction. THAT is what you look at, if they do that then things should be quite clear. Anyone can listen to something and write about it, taking it apart and running measurements is much harder to do so I default to those reviews. Some of those sites will even evaluate and tell you what kind of parts are inside amplifers, what the power supply puts out and give you an overview of capacitor quality, transister brands, board traces and all that jazz. Yes, they tell you where the amplifers, speakers, receivers etc. are manuafactured so it resembles an autopsy by the time they are done.
The good news is the information you seek is out there, the bad news is sometimes its a pain to dig around the internet to find it. A trick I use is search for something like Brand X receiver problems and if it has some, it will show up quickly.
Enjoy the hunt!