Choosing a unit that will offer you the ideal pressure for your application is extremely important.
Using a pressure that is too high for your required job can result in damage to property and can pose a safety hazard. Using a pressure that to too low will cause poor results and waste both time and money.
From a safety aspect, it is important to be aware of the Class of the unit you are operating, as operators of Class A and Class B units require specific training in order to be compliant and meet AS/NZS Standards.