Samlex Inverter Power Draw Question

I’m not as knowledgeable as many of you. Because the MW was on a 20 amp breaker by itself I assumed it needed up to 20 amps. The specs of the 2000 watt inverters I saw were up to 15 amps. I assume that more expensive units might have larger capacity. The Samlex is considered a mid-level quality inverter as I understand the recommendations. I was leery if the cheapest because there are many comments about them not lasting. This one was $860 on Amazon Prime. I like getting the item relatively quickly. I’m not using the plug ins on the inverter itself. I have it hard wired to the transfer switch that is only operational when the shore power and charger are off. I don’t have to remember to turn off the charger. The Samlex has an optional hard wired remote that allows me to turn it on and off and reads the stats such as voltage and amp draw. SOC is on the Victron monitor.
I have not had a chance to test running the inverter longer with a high draw heater. I’m curious if the fully charged battery can take more inverter load.