The potential drawbacks to a wireless solution include environmental factors. The terrain may eliminate wireless as an option. Severe weather, such as torrential rains, can adversely affect signal transmission and temporarily down the link. Similarly, the link might be susceptible to other radio frequency interference. Dense fog could possibly be a problem for microwave links.
Some reports indicate that microwave links can be more reliable than leased data lines.
Below are links to other information concerning wireless computer networking. The first link is to a site which reports on a National Science Foundation project designed to demonstrate the usefulness of wireless networking technology in education.