There's also the significant caveat with 2 that it's only "continues to work the same way" until everything changes all at once because you now need to update to the next version of Debian.

The "everything changing all at once" thing is what eventually drove me to arch (as the most popular at the time rolling release distro - and more stable at the time than debian sid), I'd personally rather have smaller breaking changes more frequently. Though it's probably less painful now to update debian versions than it use to be because things generally work better without configuration than they used to.