Until the used market completely dries up, you can still find someone who will sell you a KMA-20. The KMA-20 may have been a cost effective, reliable unit at one time but unfortunately its time has passed. Most older avionics units have become increasingly challenging to repair as the manufacturers discontinue support and cut off the supply of service parts. Likewise, even if you can find a KMA-20 in working condition, it usually has little or no warranty. Instead of continuing to invest your money in obsolete technology and delaying the inevitable, Southeast Aerospace suggests upgrading to the KMA-24. Investing in the KMA-24 will provide you with an audio panel that includes warranty and support for many years to come.