After learning of the networks available around (1 Orange 3G antenna height 6km in open field), I opted for a prepaid Orange Let's Go card (the house being rented in season, it allows tenants to access Internet according to their needs by buying a recharge at the village newsagents, or by credit card on the screen).
On the receive side, you get a very decent speed 3G (given configuration) of ~ 1,3Mbps / 300ms, machine inside and source antennas (not 4G on the pylon [for now] but home first test do not show particular problems with flows ~ 35Mbps / 120ms).
WiFi side, no worries, it goes through walls (stone, bricks, concrete blocks + formwork drywall), good reception in the house and garden.
I also tested the multi-wan function (disabled on a router Freebox v5, connected to the input of the D-Link WAN, 3G as backup connection) with a # ping 8.8.8.8. You sometimes lose a packet switch connection but quickly 3G simulating a failure (unplug the line taking the Freebox on) although the latency lengthen (that remains of 3G / 4G).
By cons, do not dream, if the WAN connection jumps while you watch TV via ADSL even if you access the Internet, it will cut your program (the dependent services of ADSL ISP).
In online game, for Xbox 360, avoids the disconnection but big lag strokes can be felt.
In short, I highly recommend especially for equipping an isolated house (still take the time to learn about the coverage and the position of the antennas), that to have a backup 3G / 4G connections to avoid interruptions (in particular parte) .
