I prefer to avoid review sites as you have no control over the people leaving reviews.
Here are a few questions to consider before moving ahead:
1) How many reviews/what review average are you trying to repair?
2) Have you resolved the issues that led to the reviews in the first place?
3) How many units do you have at Amazon? If it's a small amount, one option is to recall the stock, create a new listing and then send it back in under a new FNSKU.