Daikin premium inverter VS Standard Inverter

Hi

I am currently looking at purchasing a Daikin ducted unit for the home and not sure if the premium inverter is worth the extra money vs the Daikin Standard inverter?
How does the premium differ from the standard?
What extra features does it offer ?
How much more power savings does the premium offer? Do both models have variable drives on the compressors and indoor unts?
Whats more efficient to install 2 seperate units for a 2 storey home or go with either units?
Cheers

Using 2 separate units would be more beneficial.

most of the differences relate to operating at lower ambient temperatures or with extended pipe runs.
the heating or cooling capacity remains the same, i.e. a 10kw will give 10kW output either standard or premium.