The only review that anyone can ever trust, is the one they do for themselves while actually holding the item being reviewed...
I would always use these sorts of reviews as an aggregate - pick the info that you are curious about, then go physically try the device somewhere to see for yourself.
It doesn't matter *who* does the reviews you read - they are all skewed in one way or another, as personal opinion is exactly what the reviews really end up being. Even if they have numbers showing decibel levels etc., how the phone actually sounds in person will be all that counts.
My opinion? I think it has pretty good speakers for a phone, and am happy with it.