Interesting questions. I know I've been swayed by one review. I think if it is strong enough and convincing enough vs. just one line - "it was great" I'd go with a negative that explains why. For ex. my juicer had some great reviews and one bad one but I went with it anyway because they bad review explained just what would happen (which it did) but I was willing to live with it because the positives made up for the one negative.

One negative review would give me pause - I recently bought something - I have no idea what right now - with mixed reviews. The negatives could have scared me away but the price was probably good (Oh maybe it was my Vera Bradly pocketbook or the jewelry - whatever) and as long as I can return it then I'll take a chance. In your case the negative review made you realize something you hadn't so that held a lot of weight in your mind. Jo