First, you can not start the configuration without Internet Explorer, so without a post on Windows. Even without Firefox extension is not recognized. So forget Mac, Linux, etc.
Then big problem to connect with Neufbox SFR impossible to IPV6. It'll be cotton with sites that have this type of IP. There is a procedure, complex enough (so that if you make a mistake you lose access to the router completely and must put it back to factory settings with the red button on the back).
The solution for the ipv6 with Neufbox SFR (and probably any other router modem loaned by other ISPs), is to mount the cascade-lan lan (you can find documentation on the basis Linlsys of knowledge, translated snatches French or in English in the original Again. an error in the procedure and everything is start from the factory settings). The procedure is not simple, and you lose some of the functions of the interface, such as firmware updates and the ability to install a USB port on networked printer.
We must therefore choose between a full internet access and a functional home network.
Also contrary to the description there is no possibility of this day to install a third-party firmware, the wireless drivers being Belikn owners.
DLNA is catastrophic: Twonky running on a server, it does not handle subtitles and plant regularly, resulting in the freezing of the connected device (in this case my blu-ray deck).
In-lan lan (single functional mode on a French box), you can not use the Smart Wifi smartphone apps (they do not detect the router) ... and mobile browsers by default are not recognized, so do not allow to display the interface. One exception: Maxthon with the AU (user agent) set to "iPad" allows the display.
Otherwise the two wireless bands work very well, the trendy HDD USB3 is available everywhere (including with Ghost Commander BSplayer and Android) and allows file sharing implementation carefree. Both Gigabit Ethernet that offer comfortable 5GHz wireless transfer speeds for large files.
Other less severe drawbacks: the restart since the interface is ... sometimes.
The extinction of the front lights is also capricious: some lights come on again after reboot ...
At that price, because of the great difficulties of software configuration (insurmountable after a month of testing and discussion of Linksys and Neufbox forums, and various technical sites on the management of routers and networks) and the absence of free alternative, I can not advise buying this router for now.
Needing to the printer from all connected devices, I sacrificed the ipv6 (note that if the box is connected in bridge, Linksys, even after manual adjustment, has no internet access. I have Fears for professional servers).
The material is promising, but terribly immature software (or exceeded as DLNA) and no free alternative.
[Update] On July 30 Belkin confirmed the inability to install an open-source firmware because of the owner's driver wifi router. Note that this driver is quite catastrophic, because it does not handle new wireless standards (802.11ac), including the 80MHz band. The result is very disappointing: for example the transfer of a 2GB file on a hard drive (WD) USB 3.0 connected to the router supports Gigabit 27s against ... 14mn in 5GHz wifi!
[System Update 12/11/2014] A new firmware brings significant improvements on Wifi and better compatibility of the SMB protocol. Still no free firmware stable release.
I still do not know if the Wan2Lan operates ipv6, since I have a stable and functional Lan2Lan (but no possibility of self firmware upd or network printer, or access to mobile apps) I n ' dare touch anything.
I have put a little note to 3/5 accordingly.