How safe is Comodo Sandbox?

Is it as good as Sandboxie? Is it Comodo own technology or what is it based on?

As good or even better IMO. Yes it’s Comodo’s own technology.

Sandboxie is considerably more configurable, but as I’m not the sort that does sandbox leakage testing, I can’t really say if one product is more robust security-wise than the other.

I do know that the developers of CIS feel that their sandboxing technology is far superior.