The problem with Rich Snippets currently is that we currently don't know if they improve SEO, Google is always vague at best and has said it does not. But from what is reported Rich Snippets do help things like:
- Drawing a searchers attention to your site in their results.
- Provides instant useful information to what they are searching.
- Increases click-though rates.
- Decreases bounce rates.
Basically you should see Rich Snippets as providing even more information before they click. People are more likely to click your page if they feel its more what they are searching about and never-mind the fact that rich snippets also standout.
I believe that maybe one day we will see Google rewarding sites for rich snippets and believe that webmasters should make the changes now so if they do start rewarding then you are at the front of the queue.
With that said and rankings a side and going back to what I said about SERPS, its nice for people to have things like review stars and other information, currently Google does not display a lot of the rich snippets in their search results but from what I've read this is due to extend.
So in short my advice would be to use Rich Snippets as they are pretty easy to use and it wouldn't hurt your rankings and at a later date may help.