For the command-line selection mechanism of numerix.py to work, the following change is needed:
if which is None: ## Add this line
which = rcParams['numerix'], "rc"
Otherwise, the rcParams value clobbers the command-line value.
Update on pcolor_demo2.py: strange things are going on, but now, using profile.py, I get 2.72 seconds with Numeric and 9.49 seconds with numarray. I don't have any explanation for why it was taking 80 seconds with numarray when I tried it earlier today. It is still much slower than with Numeric, though, which seems odd.