Few years back, it would be beneficial for content posting. But for SEO its not worthy at all. Better try not only to write unique content but...
Check Google Webmasters for any message from Google. also use third party sites avaiable for Panda/Penguin Check and using your analytics data...
Domain Age is better as it helps to do better in search results and most important thing is "brand" Its a good chance the the old domain has...
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