I don't think it's possible to get an unbiased firearm review from a commercial publication.
But not for the reason most people believe- that a given magazine will tend to publish glowing reviews of products made by the companies buying ad space in the publication.
That may be true to some extent, but isn't something I have a problem with.
I fundamentally don't think it's possible to test a given firearm properly simply because it would be a very resource intensive proposition.
Even firing 1,000 rounds through just about any decently-made modern firearm is hardly more than breaking it in. In order to really do a proper review of a firearm, you would have to fire literally tens of thousands of rounds through it. The monetary cost of doing this would very quickly come to outweigh the money being paid to the reviewer to write up his article.
On top of that, how many people shoot their guns that much? The average gun owner is going to shoot maybe a couple of times a year. Heck, even someone who likes guns and shoots regularly probably isn't going to burn through more than a case or two a year.
So there's no financial incentive to really put a given firearm through serious testing for people who aren't going to really shoot their guns that much.
The bottom line is that nearly any modern, properly-made gun is built so well that they're likely to outlive their owner. Most of them are built to tolerances that make the potential accuracy of the gun better than that of the person wielding it.
Basically, no matter what gun you buy, it'll probably work just fine, so the main reason to go with this-or-that model is going to have much more to do with personal preference than anything else.
As for how I evaluate a gun? I just look for the guys whose guns have the finish just about worn off, who shoot on a continual basis, and then I ask them what they think. That's the best review you could hope for.