1) Buy? No. Try? Definitely.
2) Depends on the content of the review. If the details check out, then I'd be wary, but still would want to hear for myself. I always ask myself if the person I'm reading has the same tastes I do. In most cases I don't know. In most cases when I find out, the answer is no. So I'm still left to make up my own mind.
3) Can't answer that. Best bet is to suspect everyone as being a shill for some company, an editor trying to make advertizing money for his periodical, or some gear religion (not talking about religion religion) with an agenda and to make up my own mind based on real first-hand experience.
Never trust anyones reviews, not objective enough. Publications that accept advertising, get review samples from manufacturers, and/or attend trade shows have too close a relationship to manufacturers to provide usable reviews.
I will read them, just to find out specs, but I don't trust any of them..
Every guitar mag will deny it to no end, but the truth is very simple: They absolutely tailor reviews to their advertisers. This means they highly play up any positive features of the product, and totally soft pedal any negatives. I know writers who have been forced to rewrite reviews to make them more positive for an advertiser's product. Add to this that most writers are probably making $75 - $150 for a product review, tops, and it's just not worth the effort and aggravation to argue when the editor demands a rewrite. I don't know if it was always like that, but it sure is like that now. And when editors come on guitar forums denying it to the hilt, they are lying.
It always made me mad to see all winners numbered from 1-10 rather than just saying some suck and some don't. Point out the good things yes but point out the bad when it's justified and not based on the money those companies spend with the magazine. It really is about money and favoritism.
I use reviews to let me know the ballpark that the product sits in. They usually give a good idea of where the strengths and weaknesses lay and whether I might be interested.
After that point, if I think I might like it, I start my real research at the guitar store. If it's something they don't carry, then I check for Internet soundclips next, and then check people's thoughts here.
A magazine review is a starting point, definitely not an ending point. They are far too positive about everything to make it the gospel.
Magazine reviews are based on how many advertising dollars the manufacturer spends, rather than the merits of the product. I have seen some great reviews of gear that was absolute crap.
It's always been this way, and it has to be. A magazine cannot give a bad review to a product that's advertised in their publication or they will loose revenue. It's the same for all magazines, be it guitars, cameras, motorcycles or whatever.
The amazing thing is that according to the poll so far, 63% of the readers think the reviews are honest.
I chose the first option. That doesn't necessarily mean that I think all reviewers are lyin' bastards, but they would have absolutely no clue about my preferences etc. I'll listen to what fellow musicians that I respect have to say about things, but why would I trust some writer to be a good judge?
I absolutely hate the Guitar Player video reviews on their website (GPTV). Combined with some of the lamest guitarists you could ever find, they spend all of the time giving specs and little time doing actual sound testing which is probably good since most of the demonstrationers are not very good or are at best extremely average players. Its amazing that while they are reviewing products there is tons of distracting background noise. It sounds like a Saturday at Guitar Center.
Even though most manufacturers demos will of course be slanted toward their product, Ive found that actually provide reasonably close to the truth sound samples played by excellent guitarists. The Roland/Boss product videos are great.
I can say that I've had pretty good success buying into the reviews. I got my Reverend Hellhound head because it got 5 stars from Guitar Player for tone. Paired with my Eminence Governor loaded pine cabinet I'd give it a 5+ stars. Got the Bad Monkey because one of the mags rated it very good and low and behold it IS good. I'm still pretty skeptical but so far so good. Take it for what it's worth.