I would usually jump to the answer and say NO, however there are times when posting a rebuttal is your only option. However be warned that a rebuttal just like the report is never removed and is a permanent addition to the page.
When to post a rebuttal on your ripoff report page
Posting a rebuttal is really not recommended unless you are 100% certain that you have no future plans of trying to push that ripoff report link down search results. Adding a rebuttal is adding content and refreshing a page in the eyes of Google, so the link and report page will or may rank higher or stronger on Google. Also there is the chance that the original author adds more to the page by responding to your rebuttal and then it becomes and active thread/discussion which can lead to more harmful words and also tells Google that the Ripoff Report is interesting to internet users. Adding a rebuttal will make it more visible and more people will see it. Add one at your own risk but if you never plan on getting rid of the report then by all means!