[Q] CM12.1 nightlies to CM12S

Hi everyone! First of all, I was wondering if is it worth it to install CM12S having already CM12.1 last nightly; and if you say so, is it enough to make a clean install and flash the CM12S zip? Cause I don't wanna mess it up forgetting about flashing the correct boot.img or something and make my One a wonderful paperweight.
Thanks! :)