One of the benifits of having a wireless network, is not having to run wires in the house, however you have to bear in mind that wireless is not as fast as ethernet, furthermore encryption will also have some minor impact on the wireless throughput and in addition the more devices connected to the wireless the more overhead it will experience.
In terms of realibility, wireless will suffer from interference caused by other cord-less devices, so it is very important to establish whether there will be other wireless devices operating in your house or network ensuring that they are not operating on the same channels.
However if you want a wireless network operating 24/7 without any downtime you could look into wireless load balancing, which distributes the load across multiple wireless access points, increasing reability and reducing overhead on the network.
Hope this helps.
Regards,
Infiltrator