Low-pressure cylinders are common in New Zealand and work well in most situations.
High-pressure cylinders are more expensive, give faster flow and allow you to use a wider range of taps.
But this increases the water and energy used. High pressure systems can be made more efficient by using water efficient showers and taps.
These have lower water flow than standard taps and fittings but are designed to deliver the water effectively and comfortably. High flow showers do not always equate to better showers.
There are some low-pressure cylinders which give you high-pressure delivery. These are called indirect mains pressure cylinders. They are often operated at high temperatures, so standing losses can be high.