Two sites EMD - One is Plural Version of Keywords - Should I 301 Redirect One of the SItes?

[dwzemens]

I have two fairly new Adsense niche sites with the same EMD name key words with the exception that one is the "s" plural of the keywords.

Do you recommend trying to keep two sites active or 301 redirect one of the sites to the other? If so, which site would you redirect and how would you determine which one to redirect?