Router has ability to transfer data at faster rates, but will only run as fast as you can feed it. Hence if 45mpbs download is max from your WAN connection most you will see into house is 45mpbs. Internally though is a server or transferring between devices now the 1gig weird or faster wireless transfer rates can come into play, assuming of course your source device connection types and receiving source can manage data rates at higher speeds. Best way to think about this is router is unlikely to be bottle neck.