Stereophile only reviews the products that are offered to them by the manufacturer or authorized agent for that purpose. Their website explains their review guidelines for gear, and it's about the same as that of the other audio magazines.
I do know that there are some manufacturers that will not send review samples to a particular magazine or magazines, and I have a friend that builds highly regarded tube amps and preamps who will not sent samples for review to anyone period. He's not the only one in the industry with that attitude in regard to reviews.
Let's face it: any review that you see is subjective and based on the tastes of the reviewer, no matter whose product it is. The reviews are a good way to find out about something new that is available and where to find it. But I have never been silly enough to make a purchase based on what anyone else had to say about it. I try to satisfy my own ears and pocketbook.
