Email Router v/s server-side synchronization of email

Hi,

i was google to install email router and came a cross link which says Instead of using the Email Router, consider using server-side synchronization. anyone put some light server side synchronization over email router, what are pros & corn, which one is best suited and what are the recommendations.

https://technet.microsoft.com/en-us/library/hh699800.aspx?f=255&MSPPError=-2147217396

Thanks

iffi