I got my Midland WR 300 at Wal-Mart for about $30. It was very easy to program with the S.A.M.E. code for whatever county you want. I programmed in the codes for both Marion and Sumter counties. It is not necessary to take them to a fire station for programming - just follow the easy instructions in the manual.
My Midland is A/C powered and has the 9 volt battery backup.
Last week, it sure got a good workout with the weather warnings. The red warning light was on, the readout said Tornado Warning, and the alarm announced what was happening in the area.
It gave me a good opportunity to stand in the middle of the golf course to try and do a video clip of a tornado for YouTube.
(Oh come on now, that was supposed to be funny!)