Didn't Comodo fix the minor issues with default containment? For instance, a malicious program could change the wallpaper or create a text file on the desktop. As far as I know, there hasn't been a single known breach of default containment. Containment or restriction levels don't matter unless users actively engage with containment or analyze and respond to programs running within it. The "Block" action is preferable for most users, as it maintains usability and avoids any negative consequences.