I'm using a scantenna for the digital statewide system in arkansas and I'm getting three out of four tower sites in my area that are 700/800 MHZ...The scantenna doesn't work really what I'd call GREAT on the 700/800/900 bands, But it's GREAT on the VHF HI 150-170 range area, I'm hearing places that are 60 miles away, Clear as a bell, No problems, Not sure about 400 MHZ trunked systems, I've got two in my area right here in town and they're coming in very well also...If I were you and you weren't trying to pick something up extremely far off in the 800 band I'd go with a scantenna..If you're looking towards the 800 band and it's close, it should still be ok, But if it's farther off and it's in one direction and not a WAN (Wide Area Network) then you should be ok..If it is and there's one specific area you want to monitor, I'd shoot for an 800 mhz yagi!! i don't own one but I hear a LOT of GREAT things about it as with the scantenna, I've heard lots of great things about Both! That would be my first suggestion, My first choice as well...