I have spent a considerable amount of time over the last couple of days messing about with RSS Aggregators with various levels of success.
In the end I have opted for the super simple ,and by simple I mean simple but powerful, WP RSS Aggregator by Jean Galea
On the options screen you enter your feed names and urls
Thats it then add this shortcode into your post/page
wp_rss_aggregator enclosed in  thats it.
The shotcode accepts the following parameters
Exanple usage again enclosed in 
wp_rss_aggregator date_before=’<h2>’ date_after=’</h2>’
The RSS Aggregator Plugin as been downloaded 23,535 times and is rated 5
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