[Schiphol]

I once tried to do meaningful work and, while things such as the NDSolve[] function are positively amazing, programming in Mathematica (which means using its editor) is a huge pain when you are used, say, to vim.

In the end I moved everything I had to the Python scientific stack and I'm very happy I did it.

[szhorvat]

You need to get used to the notebook concept. In the end you'll find that it's much more convenient for interactive work than a traditional command line. For non-interactive work you can still use Vim if you like.

In fact Mathematica shows its advantages most when used interactively (compared to languages, like Python, which were not really designed for this).

[ihnorton]

Python and Julia have a nice interactive notebook: IPython/IJulia.