DELL External Harddrive PDA500A USB 3.0 vs eSATA port?

Hi

I have an externall HDD from DELL , model PDA500A. It comes with an adapter from USM to USB and therefore it has USB 3.0 connector.

I have a router that has both USB 3.0 port and eSATA/USB 2.0 port.

I know that eSATA is made specifically for HDD but my external HDD does not have this port.

Is it better to use the USB 3.0 port, or should I get an adapter to use the eSATA port of my router so as to accommodate better for specific HDD application?

Thanks!