Restoro and CCleaner both compete in the same space, but they optimise for different things — broadly, automated repair-diagnosis vs manual cleanup toolkit.
What Restoro is
Restoro is PC repair and optimization utility. Choose it when that specific strength matches your primary need.
Where CCleaner differs
CCleaner approaches the same problem from the other side of that trade-off (automated repair-diagnosis vs manual cleanup toolkit). Teams whose priorities sit there tend to be happier with CCleaner instead.
How to decide
List your top three requirements before comparing pricing pages. Trial whichever matches requirement one, and commit only after running your actual workflow through it once.