Modified wave inverter is slightly boxed off wave.which sometimes will lack of clarity.then damage the appliance.especially the appliance like TV or air conditioner. In this case pure sine inverter may be a better solution, then you can have a better quality output. But modified sine inverter was more cost effective than pure sine inverter. Pure sine wave inverter canl provide the best electrical current,as well as it will be more expensive.
So, Before you choose the inverter.you should check the requirement of the items that you want to run by the inverter. So, you will make sure you are buying the correct inverter for your needs at the start.