Will the 5814 perform as well as the other door/window contacts?
Yes. They will perform just as well as any of the other 5800 series wireless devices. There is a common misconception that just because the transmitter is smaller that it won't be as effective.
This contact contains the same transmitter module as the rest of the 5800 Series line of devices and will be able to communicate to a distance of up to 200 feet away from the receiver. If you need to extend range or boost signal then you could add a repeater.