High Head Pressure

In the descriptions of Toto G-Max versus PowerGravity flushing, the only difference appears to be 'High head pressure to maximize flow rate'. I have to admit I'm not familiar with the term 'high head pressure'. I looked around the FAQ's and forums and could not find this term defined.

Can someone please provide a definition as it pertains to the Toto units and whether this is relevant to a household running on a well and pressure tank setup as opposed to the higher pressures you get from a public water supply?

For that matter, does a well/tank system even factor into the purchasing decision for toilets?

Thanks
BMK

Anything with 20 PSI would work.
I'm sure your well system is at least 35 PSI.
With a toilet, anytime you raise the height of the water, it will drop quicker.
That's why some of the new toilets have such tall tanks.
For Toto's G-Max, they do keep the water higher in the tank for just that reason.