In Stata 12, it is much more difficult to draw a SEM diagram. You should use syntax instead.
The advantage: it allows to take into account effects of research design (survey, for example), estimation is usually better.
In AMOS 16, it is much easier to draw a SEM diagram. It is also much easier to interpret outputs because you can get everything (goodness of fit statistics) in one go. However, if your data need to be adjusted for research design, AMOS does not have any function for it.
Conclusion: if you know that research design is not a several problem, use AMOS, otherwise, use STATA 12.
