When the Xantrex went out in our Rv and Xantrex told me they no longer support the Rs 3000 I wewnt to the Magnum, It has more plug and play options you'll like with solar like Ah meter, I did have to increase the air flow capacity in the storage bin it was located, the Rs3000 being 3000watt pure sine and the Magnum 2812 is only 2800 watts of pure sine but I've never maxed it yet
at the time these people had the best price
https://www.imarineusa.com/MagnumEnergyMS2812.aspx
now as your doing a new install, do you have 2 breaker boxes?
are you familiar with installing one completely?
In my breaker box there is a 220 breaker 30amp that feeds the inverter
the inverter feeds another breaker box, sub panel, that has the circuit's run off the inverter