User report on new ASUS RT-AC 66U router

I recently replace my old D-Link DIR-655n router with the new ASUS RT-AC66U router. After about a month of use, here's my review.
Short answer…VAST Improvement!
First my set-up. I live on a ranch with 4 houses and several outbuildings clustered on 25 acres. At any given time, there are 2-4 generations of family living here. We all share one Cox cable internet connection. The router is located in a window of one of the outbuildings facing 3 of the houses. Distances can be over 300' through many walls and in most cases there is an olive orchard between the houses. Can we say extreme test conditions?
The old router, the D-Link 655 was situated in the same location as the current router, but the D-Link was connected to an external high gain 3 antenna mounted on the outside of the outbuilding. The current router is mounted inside in a window with its standard 3 antenna array attached directly to the router.
Speeds and reception varies depending on location. With the old router, there were many rooms in 3 of the houses that did not get any reception and when available only at low speeds. The fourth house did not get any reception. Rain and wet leaves on the olive trees played havoc with connections. When accessing the internet from my house, I would be glad for download speeds on 12-18Mbps in the best location, line of sight of router. Now I get over 32Mbps download and 5Mbps upload even when it is raining like today, through the olive trees. I can also stream 1080p video in all rooms of my house where before I was lucky to get any connection whatsoever in the back rooms. This is true in the other houses as well.
I addition, the RT-AC66u is a concurrent dual band(2.4/5.0Ghz) where as the D-Link was single band usage. The 5.0Ghz band does have distance issues, but is accessible. The 2.4Ghz band has much better throughput in most locations. Other advantages include being able to set up to 8 total channels; 4 channels per band so setting up separate guest networks is simple.
The ASUS GUI is fairly easy to use to get the router up and running. Be sure to update the FirmWare early on. One issue with this particular router is ASUS is still tweaking the FW, a lot. Supposedly, ASUS is working on a major FW update, I'm on the 3.0.0.4-2.70 vers. There are also 3rd party FW available that let you tweak to your hearts content if you so desire. Playing with the radio power settings might get you better performance.
Ironically, none of the computers/devises on the ranch are currently AC radio equipped, all running on 802.11n. Just preparing for the future.
In all, the investment was well worth it.
Hope this helps, Greg

I did Greg. Thanks! I have a D-Link DIR-655 and I was looking to replace it with a router that supports IPv6 so that my stupid iPad mini and iPhone 5 can communicate with apples servers without constantly dropping their connection.

I will definitely consider the ASUS you've recommended.