The older scanners do work but you may miss some traffic depending on if you live near several towers or are in a spot where you can receive multiple towers, I had a BCD325P2 and it worked okay but there were lots of spots I wouldn't hear it, I did have an SDS100 and it worked good but the price is steep and with some of issues it has like the cold solder joint and the scanner getting warm/hot I decided to part ways with it, I now have a Unication G5 which is built as a pager for public safety and is no means a scanner but if programmed properly it does great on P25 simulcast systems but again it has a steep price point as well