Wireless Keyboards and Mice?

I'm considering getting a wireless keyboard and mouse. I'm looking at
some IR devices from Microsoft and Logitech. I have several questions:

1) How good are wireless keyboards and mice?
2) What are the drawbacks and things to watch out for?
3) How often do the batteries need to be recharged?
4) How many recharges can the batteries take?
5) When the batteries can't be recharged again, do you have to buy a new
device?

I will be installing a wireless network later this year, so I don't want
to get any Bluetooth devices. I know that Bluetooh is all-band
interference for WiFi devices, which can be a problem for wireless
networks. However, theory is often different from practice. I've heard
good and bad when it comes to using both Bluetooth and WiFi devices in
the same location, so I'm curious as to how well Bluetooth keyboards and
mice will co-exist with WiFi networks in practice. Do they interfer with
the network? Would the signals given off by the WiFi access point
interfer with the Bluetooth keyboard and mouse?

--Tom