Welcome Rob.
Sounds like this is a huge system you are planning, have you considered how much battery power and later how much solar power you’ll need to feed such a huge inverter, in other words have you looked at the system as a hole, the big picture financial and otherwise?
First thing I’d do is look at what happens to the system design and cost if taking the aircon out of the picture, in other words if the aircon is a non essential only to be used when the Eskom grid is available.
If you’ve looked at the big picture and system as a hole and you’ve got the financial means then by all means go for it, but as others already said you can choose a lot better than Sunsynk.