Pager coverage is actually pretty damn good. Come to think about it, I had less issues with pager coverage than cell coverage even though it was obvious they broadcast pages cross a given region, a few states or cross the nation wide network. Service was pretty damned reasonable, about $8/month or so IIRC, about the same as unlimited texts on t-mobile.
Why did I ditch it? Well the pager networks got bought out by other people, changed hands, and they no longer offered some of the handy dandy services they once did, which would include web->page and or e-mail->page without adding a ton of formating data. As in, one could attach a pager to a page reader via TTL serial and issue commands remotely. Mucking with the system resulted in too many garbage characters, and I could either revamp the system or go with something internet based.
But pagers still have their use. Coverage is still pretty damn good.