Personally, I have never broken out when switching cleansers. But I will say that switching to gentle-er treatments always carries a less likely chance for breakouts as opposed to upping the treatment with harsher/stronger stuff.

Basically, if cetaphil or cerave are your choices I think you should do just fine

If thats all youre using for your acne then if you stop using it then youre acne will come back, simple. If your skins doing fine with it then just keep using it (if it aint broke...)