I used SPSS at my last job, and I liked it quite a bit. There were certain tasks that were much easier using the windowing interface, and SAS's code-only method just doesn't quite match that. For example, transposing a dataset in SAS is not very intuitive. In SPSS, however, the wizard explains which variables to choose for identification of variables, constants, and variables to transpose.
Then on the other hand, SAS is quite powerful and is capable of a lot more than SPSS. Perhaps SPSS's code module can be used in a similar way, but when I used it, it was rather annoying. If you need to use a dataset, it required it to be open. In SAS, you don't ever have to open a dataset, unless you need to figure out what the variables are like. Then again, you can just look at the column information in the context menu. SAS flows from one dataset to another, and there's no need for the dataset to pop-up when using it.
SPSS was much better at handling variables (columns). Variables could be easily changed from one type to another, and "labels" for particular variables could be applied. For example, 1 = Low, 2 = Medium, and 3 = High. This can be accomplished in SAS with formats, but it's not quite the same, as it requires the user to apply the format. SPSS was also quite useful for turning a variable into a category or a variable with ranges; for example, converting salaries into salary ranges. A window wizard helped with that too.
At any rate, it will be interesting to see what happens in this market now that IBM is going to own SPSS. I always thought SPSS and SAS joined together would be a really great product, and perhaps IBM will bring to SPSS more SAS-like capabilities. Who knows?
More comparisons of SPSS and SAS:
- A Guide to Statistical Software
- Comparison of Data Analysis Packages
- Comparison of Statistical Packages