The review/survey has become a direct tool for the consumer to judge who they are willing to do business with but is everything put on the Internet the truth? The answer is YES. When a consumer feels a certain way and strongly enough to take the time out to write about it, it is their truth. 

A way to head off any bad spirited reviews/surveys is to ask for one before they leave. You will instantly have a feel for how that's going to go. At that moment if there is any angst or bad blood boiling, handle it. There is no reason to wait and "hope" that they will be "nice" during the review process if you haven't completely earned it. 

Having bad reviews IS costing you money and you can't really quantify it because no one comes in or calls and says "hey, I didn't buy from you because your reviews suck."  

The future is now and to maintain your dominance simple things like VALID positive reviews must be top priority.