Chuck,
If you have to replace the inverter, consider a Magnum Pure Sine Wave unit. I replaced my Xantrex with a MS-2012 unit after having issues with my Samsung reefer. It worked flawlessly and was easier to operate than the Xantrex unit. That said, if you are not planning on ever installing a residential reefer and are satisfied with the operation of your current electronics, a modified sine wave unit is probably sufficient and less $ than the pure sine wave unit.
Steve