Is the Avast Sandbox good?

Or should I get some others like Sandboxie or so?

It’s good. I see no reason to use anything else.

You need to learn a few new steps.
https://support.avast.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=455#idt_09

@YoKenny
LOL. How you come up with this is too funny.

After using the process vitualization in AIS, I have complete confidence in it.