I am a huge fan of Foundation 4. I've used it forever and when they came out with Foundation 5 the daing div names all changed so I just got stuck using Foundation 4 ever since. While I know this is a question of Foundation vs Bootstrap, and for the record my vote is for Foundation because Bootstrap is just too much and Foundation 4 has everything I need! But on the question of the div name changes, and honestly I haven't looked back since Foundation 4, are they still changing the div names with each new release? While I would love to take advantage of new JQuery widgets and other improvements, I mean who wants to continually learn and change something as fundamental as div names with every new release?