I finally purchased and installed a proper off-grid inverter capable of handling my ever increasing home energy needs.
I settled for the Outback 3KW Inverter (VFX3024e), the European version outputting 220v at 50Hz.
The inverter has been installed and performing flawlessly for a number of months now. I have never exceeded it's rated output, in fact I doubt I ever exceeded 1KW of load.
The cooling fan output varies with the load demand and the current temperature of the inverter internals and therefore operation is quite. One thing I have to point out however, which is the humming coming out from the device. I installed the inverter in the garage and therefore noise is not an issue however the humming can be annoying if the inverter is installed close to the living area.