There are many types of inverters. I’ve always recommended using the smallest inverter that will do the job. Most inverters say that they have a surge rating approximately twice the output rating but we’ve found that you can’t rely upon this for most start-up applications. For many electronic or motor loads the inverter should be rated at three to four times the constant wattage (amperage) of the appliance.
If you are in need of a better converter and an inverter you may want to consider a higher end inverter with a built-in converter and 4-way battery charger. These high-end units come with excellent inverters and better converters/battery chargers than what came with your RV.
Sine wave inverters provide a cleaner form of electricity but the units are considerably more expensive. Because they provide a better wave of electricity they also draw slightly less power, which could be important for those relying on generator or solar battery charging.
Happy Inverting.