Bests & Worsts Reviews from Amazon

Amazon flagged my first review of this product because I raised questions about authenticity. They claim it is an authentic Harry's product. Okay, well why is it when I use these blades they last for about 2 weeks and get too dull, whereas when I buy Harry's blades from Target they last about 4-5 weeks? Something does not add up or seem right. I have been using Harry's blades for over 3 years. These Harry blades I bought on Amazon are bad. I would not buy them again.