For the core feature, cleaning you Mac, the best choice is CleanMyMac.
I ran both programs and CleanMyMac found 220 Mb of junk stuff while CleanGenius found 80Mb...
The uninstaller is OK for both. Even better than AppDelete, sometimes.
However, CleanGenius has some interesting features CleanMyMac doesn't:
Disk space monitor
So if the addons are important to you (and they should be), CleanGenius is a good tool. However, the core feature is not the best. Far from it.