inverter choice

I am planning to replace my 2000 watt Magnum inverter with Magnum S2812 or a Magnum ME3112. The 3112 is a modified sine wave and the 2812 is a pure sine wave. The inverter I have now is a modified sine wave and it seemed to work until now. I plan on installing a residential refrigerator soon. The question I have is the pure sine wave inverter worth the extra money? There is about a $500.00 difference.:@