The new RT-AC66U and the older RT-N66U look almost identical: Bucking the industry trend of hiding antennas inside the enclosure, both of these routers provide three removable and upgradable dipole antennas that you can reposition to deliver the best wireless performance. They're mounted to the exterior of a satin-black, diamond-plate-finish plastic enclosure. The routers can lie flat, sit semivertically on the provided stand, or be mounted to the wall.

The RT-AC66U provides two USB 2.0 ports, so you can attach both a USB hard drive and a USB printer, and then share the devices over the network. I didn't evaluate try to connect a printer to the router's USB port, but the RT-AC66U was very fast at transferring files to and from an attached 500MB 2.5-inch USB hard drive. Asus is working on a new Android and iOS app called that will enable users to sync, access, and store data on an attached hard drive, using a multitude of devices over the Internet. Update: Asus has since released new firmware that enables AiCloud. If you've purchased an RT-AC66U, you can download the firmware . According to Asus, AiCloud will also allow you to access any PC on your wired or wireless network from the Internet without the need to install client software on each machine. I have not evaluated this new firmware.

Whether you plan to use your router to stream media, to host files, or to download files using P2P services such as BitTorrent, the RT-AC66U has you covered. It offers and iTunes servers for video and music, ftp and Samba servers for file hosting, a pass-through for secure remote network access, and a program called Download Master for downloading files to an attached storage device, without requiring a host PC.

This dual-band router can run a 450-mbps 802.11n network on the 2.4GHz frequency band and a 1.3-gbps 802.11ac network on the 5GHz frequency band simultaneously. The RT-AC66U I tested arrived from the factory with its 5GHz radio configured to deliver 80MHz of wireless bandwidth (draft 802.11ac).