Tried it. Not even close to a MATLAB replacement even for students. It doesn't support or doesn't name half of the statistical functions the same thing, which makes it useless for problem sets (where you have to turn in your source code).
No, often the code is slightly different and doesn't run correctly in MATLAB. The last time I tried was December for probabilistic signals and random signals. I'm the student so the problem wasn't me, it was the TA's who ran the code and gave you a perfect score if it ran and produced exactly the same results or a zero if it didn't produce the same results.
Personally, I use sci/numpy for all of my statistics/numerical analysis needs.
