I am designing a new 5.1 studio, what monitoring system is appropriate?

Speaker System Selection Guide:

The main objective of this product selection guide is to prevent the customer from making basic mistakes when selecting products for the application. It is specifically designed to give a suitable SPL for music, movie and broadcast studio applications. Other applications, for example, Sound Reinforcement or Fixed Installation, may need more or less SPL.

This system prevents monitors being used in rooms that are too large or at listening distances that are too long. The recommendation allows larger monitors to be used if the customer desires. The advantage of 'over specifying' monitors is that distortion is reduced for a given SPL output, directivity is better controlled and the midrange becomes smoother.