I would make sure to make a save point, before changing. Sometimes, switching can have unintended side effects. Your conscientious Sim might not be as good of an employee, when you return, and you might find your Sim with a new girlfriend/boyfriend or having dumped a significant he or she formerly had. You might find other other anomalies, in the Sim's relationships. The longer you leave your Sim, to his/her self, the more likely that Sim's personal life will be radically different, than when you last played that Sim. As long as you're prepared for that, rotation can be a nice change of pace. Making a save point allows you to go back, if something drastically wrong happens, though.
I haven't used rotation that much so far, other than to water my main Sim's plants, while he's at work. In Willow Creek, I would switch to Travis Scott, while my main Sim was at work, to make him a bit more useful. I also used that as an opportunity to make him go to work. That was before I learned that unplayed Sims don't normally go to work. That's a little annoying sometimes, because sometimes visiting friends act like they're unemployed & visit at all hours of the day.
