Difficult seasonal conditions during the last six years have placed many farms under significant financial pressure. Producers have been looking for enterprise changes which will quickly improve their profits. New breeds have increased the options available, but there is rarely any local production data for them. Information in the media has done little more than create confusion about the true differences between sheep enterprises. Modelling allows this complex question to be looked at in a logical fashion and combines production and financial factors in the comparison. GrassGro® was used at two locations in southern NSW, Yass and Cowra, for the period 1960 to 2007. The results indicated that no enterprise performed consistently better based on profit per hectare. More detailed work within enterprises showed that the range within an enterprise due to changes in genetics or replacement costs was far greater than the differences between enterprises. The risks associated with changing an enterprise are generally greater than from improving an existing one. It is important that advisers base their comments about enterprise choice on robust information rather than the simplistic information that circulates within the sheep industry.