[paperwork]

Honestly, just never used it (not since freshman year almost two decades ago). I mainly use eclipse and it works very well for me. I like how I can hover over a variable and it tells me info about that variable, click on it and it shows me very other place it is used. I can rename a function and it gets updated in all files where it is used. I can very quickly see where a class fits in the class hierarchy or see which methods call other methods.

Emacs might do all of this, but eclipse does this well enough.