I have a 2000w modified sine wave inverter made by Ring. I run a 700w microwave, 900w travel kettle and a 19" led tv, not all at the same time though. I also run the engine whilst the kettle or the microwave are in use. TV and laptop run with no problems at all even though its a modified sine wave inverter.
The inverter is hard wired into the batteries with an inline fuse fitted.
Hope this helps.