I get about 10 of these requests a week.
"If you send me a free laser I will review it on my blog and then people will buy your lasers!"
Riiiight, and if Ferrarri wants to send me a free car I'll be sure to drive it really fast so people can see how awesome Ferrarris are. I'll gladly send a product for review to WIRED magazine or somebody who actually has a large exposure, but these random people email me all week long, promising that if I send them a free laser they will post a glowing review on their blog about how much the laser rocks.
Problem the first: If your "review" site promises to give glowing reviews to anyone kind enough to send you a free product, what are your reviews worth to anyone? A review should be critical, not ingratiating. A reviewer should PURCHASE the product to be reviewed so that they can be assured of not receiving special treatment, and so they can evaluate the purchase and delivery process from an objective perspective.
Problem the second: Are you really so important that I should send you a laser worth hundreds (or thousands) of dollars, rather then spending that money on real advertising? Is your name Steve Wozniak? I know that you think that getting a hundred blog visits a week is a big deal, but it's not. 10,000 visits a week is not a big deal. 100,000 visits a week will be enough to get me interested, and even then I'm probably going to want the laser back.
Customer reviews that are unsolicited are the most reliable source of information about a company, which is why I like the Reviews section here on LPF. It allows people to share their real experiences with the public and share opinions on companies, products and service. A solicited review is basically begging with the promise of a good word in return, and they can't be trusted since the reviewer is now indebted to the company that sent him free goods. I'd rather see a real review of our products from a legitimate customer than grovelling praise from a beggar.