What environment? Marine use? Land use? It's getting hard to beat a cell phone but an amatuer radio has my vote. A ham radio will perform the best.<br /><br />If you are talking about CB I have no idea of a good one.
I say use the Collins/rockwell FRT-96.<br />It will do AM, USB, LSB, CW, FSK.<br />You can use it in high or low power modes with up to 10KW of output.<br />Great all around HF radio!!!