No cleaners
An old thread I happened across while trying to work out why there's mentions of CleanMyMac all over the place.
Looked for reviews: I suspiciously find they are all rather similar. Particularly the last paragraph.
From here, I gather CleanMyMac seems rushed. The support is too eager to please - drop the smileys for pete's sake.
This seems to conclude "do it yourself" which is what I do anyway, via the command line - I'm no expert guru dude, but surely "Find" isn't so hard, with a little "Grep", and "redirect errors 2 > /dev/null" is precious.
So find big files, for one.
And otherwise, I've always been happy with Onyx, freeware that helps track all finder preferences and clean all caches - Many GB saved every few months, when I remember to run it.
And it's got helpful safeguards all over - hard to mess things up.