I've been a top Amazon reviewer -- at one point I was #84 -- and at no time have I seen any reviewer complaining about someone else's review. At least not if it's an honest review based on hands-on experience. (There can be quite an outcry if it's obvious the review is fake, such as someone who clearly didn't read the book she's writing about.)

But if you give an honest opinion -- even one with which I disagree -- I'll never even downvote it, much less report it.