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For 802.11n Wi-Fi base stations, creating a roaming network is by far the best choice. This will provide the best throughput between the base stations and your Wi-Fi devices.
If you are unable to build the recommended Roaming network, then a Wirelessly Extended Network is the next best option.
For more information on this, take a look at this article:
Wi-Fi base stations: Extending the range of your wireless network by adding additional Wi-Fi base stations
Hope this helps,