The narrowbanding of analog radios should have little practical effect on transmissions. You will need to turn up the volume control a little on existing scanners. When additional channels made possible by the narrowbanding come on the air, you may have problems with existing scanners.

All studies I have read suggest that digital radios should have better coverage than analog radios at the same power levels. However the FCC has not yet set a future date for requiring digital radios. When it is set, the date probably will be ten years in the future.

Most of the problems with understanding radio transmisions come from poor microphone technique by the persons talking. People talk too far from the microphone and allow wind noise and ambient background noise to interfere with understanding what is said. Some people do not speak clearly. Many older handheld radios use the loudspeaker as a microphone when transmitting. Design compromises to use the same device for two purposes result in degraded quality of sound. Also many people transmit from inside vehicles with a handheld radio; the vehicle body shields the radio signals and severely reduces range.

All two-way railroad radios must be type accepted by the FCC. All previous type acceptances expire January 1, 2013. A few of the older radios can be factory modified to meet new narrowband standards. The rest cannot be used legally for transmitting after this date. This means new radios must be purchased and put into service before 2013.