I purchased my AK-451 ELT in Dec 2010 from Aircraft Spurce and installed it in Jan 2011. It has a two year warranty. I have done periodic tests about every 3 months. It failed to test in Feb 2012 during my condition inspection. The unit is dead, no indicator test light and no transmission on 121.5.
Lesson learned: Test your ELT on a regular basis, even if new.
Side note: After phone call to Ameri-King, ELT was shipped to them for repair. I have had several conversations with them since shipping the ELT. English is not the first language at the Ameri-King phone number. Communication has been difficult with the personnel at Ameri-King due to a language barrier. They will not let you talk to a supervisor, you can only e-mail the manager at the company address. Aircraft Spruce has contacted them on my behalf to get the unit returned. Supposedly, unit was shipped back to me Mar 9. Something doesn't smell right here!
Skyview, Garmin GTN750xi, TT Gemini AP
CFI, CFII, ATP
Guthrie-Edmond Rgnl, OK (KGOK)