I (not OP) am in the Vine program that they mention in the article. I admit that it puts me in sort of an odd position to be trying to write an unbiased review

I (not OP) am in the Vine program that they mention in the article. I admit that it puts me in sort of an odd position to be trying to write an unbiased review of something that I got for free, but I always do my best to mention in my review whether I feel like I would have paid the cost of the item, all other things being equal. For me, the most difficult part of the review is that we're on the hook to review the product within 30 days of receipt - in some cases, that's not enough time to really get a sense of how well the product holds up.