Not necessarily. SAS is a much more powerful package than PASW (SPSS) in some aspects, but it is also much more difficult to use and learn. Unless you have very large data sets or need to perform very complex statistical analysis we recommend that you use PASW. Data files can be easily transferred between the two software packages, so it would be possible to start your analysis in PASW and then later move to SAS if required. For further information about SAS, visit the SAS website.