Diaper questions

I bought 10 Bummi doublers recently with a buy-it-now on ebay for a good price. The seller said she had lots of other diapering supplies and asked what I might want. I asked about Bummis Super Whisper Wrap covers, Fuzzi Bunz, and tote bags. She told be that Fuzzi Bunz are possibly dangerous to little boys' developing testicles because of the amount of heat that is held in. I asked her for references and am now searching all over the web trying to find any information about this. So far, I consider it a rumor, but I am willing to stand corrected if there are any studies or even well documented ancedotal evidence (more than, I heard if from a friend who read it on a discussion board that one lady's friend's son was sterile). For one thing, I don't think they haven't been around long enough to tell if boys who wear them have sperm problems.