I worked about 7 years with Matlab, but at the end I gave up and I switched
to Python. This is mainly due to the fact that with new Matlab releases
(starting from R14) it is almost impossible to build a distributable
executable file. You can compile an application into an exe, but you have to
distribute such big files that I gave up. Moreover, GUI capabilities of
Python (wxPython) are much much (much)^Inf superior to Matlab ones.
Regarding your question:
They're mostly concerned about
cost and scriptability, but they're worried that the resulting Python
code would be very slow.
This much depends on how you use Matlab. If you use highly specialized
mathematical routines, image processing, optimization routines and
everything that involves large matrix computations (inversion,
decomposition, system solving etc...), I would be in doubt on which software
I would use.
Loops, conditionals and friends are much much faster in Python than in
Matlab, even using JIT acceleration.
Both software have a fast learning curve (in my opinion).
In case of large matrix computations, I would try to compare Matlab
capabilities to Python Numeric/scipy.
However, if you could specify a little bit more which use of Matlab you do,
I can probably give some more advice (even if I am not an expert with
Numeric/scipy, so my Python routines may have to be optimized by someone
"Imagination Is The Only Weapon In The War Against Reality."