[acomjean]

This.

I've upgraded bootstrap styles using "Less" which is being replaced by "Sass". It takes a little bit to get set up (the jet brains phpstorm app builds it), but once its done its pretty great.

You can also customize your download leaving out the parts of bootstrap you don't want. (I originally did that for and older version bootstrap, while keeping some of my page styles). The customizer seems to now give you a json file, so you can download updates with the same settings as your original download, I have not tried this though.

http://getbootstrap.com/customize/