[w_s_l]

is there any security concerns with the pi itself? say your computer is infected with a really bad malware. it takes over your host, ignores your right to block out noise, and then the idea that pi-hole will be able to as a last resort block it out?

[ashman5]

Some devices use hard coded DNS (looking at you G). You can force devices to use the pi-hole via masqurading. In you example, you'd be able to see the malware requests show up in the pi-hole interface.