It's $10 cheaper on Amazon (current price comparison), and there are 11,000 reviews. You might consider reading some of them to see if they address your concerns. If on the Amazon website vs. the app, you can go to the second page of reviews, and right above the reviews, you can search for whatever term about which you're concerned. I know nothing about what is giving you second thoughts, but let's say it's stomach upset--just type in stomach, and all reviews mentioning that word will pop up.