I have not recently put time into researching the best unit now available.
Is this model below the newer, better Fx or something inferior?
It was less than $1000.00.
I've presently got this one and will combine it with SPOT continuous tracking when over hostile terrain:
The AK-450 ELT from Ameri-King is FAA TSO-C91a approved and meets FCC rule for improved satellite detection. It features voice transmitting capability, visual "on" lights for both ELT main unit and remote panel, and uses standard Duracell batteries (included). Includes low drag aircraft antenna, portable antenna, remote control panel, wiring and coaxial cable assembly, handheld lanyard web, mounting tray and clamp.
ATTENTION: 2009, the international COSPAS-SARSAT satellite system will no longer provide satellite-based monitoring of the 121.5/243 MHz frequency. After the date of the satellite termination, in 2009, 121.5 MHz signals transmitted from ELTs operating on the lower frequency will only be detected by ground-based receivers such as local airport facilities or air traffic control facilities or by overflying aircraft