I have Splus, a very powerful package which is has a considerable
following in the research statistics community. The newest release,
4.0, looks to be quite usable. Try:
I would be interested in any comparative notes/comments as well.
Hanif Khalak, hkhalak at mason.gmu.edu
Institute for Computational Sciences & Informatics,
George Mason University, Fairfax, VA 22030, USA