Here in Thailand, the LVTOPSUN inverters seem like a good product. I have installed a 3kw toroidal (LF) LVTOPSUN unit--the manual for this is posted in the resources section of this board. They also have 6kw units, and perhaps larger.
The 3kw inverter is presently powering a rice cooker, refrigerator, washing machine, iron, sound system, video projector, mobile phones, a laptop, and all of the LED lighting for the house--of course, not all at the same time, but it has never been overloaded yet. It's been going strong for nearly four months now, powered by a 48-volt power wall LiFePO4 battery charged by the inverter and two separate EPEVER charge controllers.
I think the LVTOPSUN brand is only marketed in Southeast Asia, though. There are some "no name" toroidal inverters that tempted me when I was looking for one, but I haven't tried any of them, so cannot be confident to recommend them.