Everyone has a bias based on what they are happy using, which is fine as long as you take what everyone says and balance out the view.
At the end of the day you have to try gear yourself to really know if you will like it and preferably on your own kit. ie your mast to see if it works on it.
EG - I tried a brand mentioned by leech, and on his set up. I came to the beach suggesting that no one in the known universe could make a sail that bad and put it in production.

Now I know these guys make good gear so how could they get it so wrong?

Of course the sail was not bad at all, it was just leech's piss poor rigging

.
Having been able to send time on over 15 different sail types this summer I really enjoyed finding out the diffrences. I rigged and sailed a few on my masts and some on their own masts. Some sails which I would never spend my money on, are loved by others that did pay for them.
Watching from the beach no one sails any worse for their choice because they are on brand x instead of y.
Like taking sailor opinions, i think you should read all of the mag test/reviews and take an overview as they often conflict with each other, but you will get a feel for what they are trying to describe.
Also if you can find the boards mast article, you can compare mast brand types and then match them to what you are using to see what sails might work on your current gear without having to buy all new masts when you change brand. Just keep in mind that they are not always right.
Some one I know is working on an unbiased sail and board testing site with no brand attachments and maybe it will be up in time for next summer. They hope to out line the differences between products in an informative way. So look out for it soon!