wireless router g n difference

A wirelss N router make any difference to a network consisting of all G wireless adapters?

I have my Xbox, laptops and several NAS units a networked hard drive all with my mobile. Whenever you transfer files to and from a portable hard drive through network Radio over almost everything stops on the web (as another team can not even browse the Internet.) I wonder if I can upgrade to a Wireless N router that this enhances independent device performance G? I know that G has a limit of 54 Mbps, but every single device on my network to use the same group of 54 Mbps bandwidth in an N router, or if the N router to give the equivalent of 54 Mbps bandwidth to each device up to 300 Mbps N edge of technology?

there is no difference the router is connected to g in g adapters bandwidth, bandwidth between the n slices adapters.

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