An ‘accurate’ review is a bit of a misnomer since review are very subjective anyway, therefore what exactly constitutes an accurate review is hard to judge. Someone could play the game for a few hours and come up with a similar opinion to someone who’d played a game for a lot longer. Equally two people could play the game, complete it and come up with completely different opinions.
I agree that knowing that the person playing the game all the way through would certainly be reassuring, but it’s just not practically as far as print copy goes. Of course some reviewers are more professional than others, and dedicate more of their time to a game.
However, I wouldn’t dismiss print mags out of hand, what you are buying into is a lot of experience in the reviewer, which can be very valuable. I’m not sure how it works in other countries but certainly in the UK the writers lend a lot of personality and character to the magazine (although sadly not quite as much as they used to). It’s very easy to ‘get-to-know’ your reviewer, understand the direction they’re coming from, the genres they are experts in and more importantly how often their opinion falls in line with yours.