Brawl in Cell Block 99 has some brutal moments, as do Starred Up, McVicar, Scum, Bronson & A Prophet.

Malefique is a good one, similar set up to Stoic, centering on the residents of a cell but it goes a bit strange.

Wouldn't say any of them were disturbing or extreme, but all solid films.

Also Oz the TV series has it's share of violent scenes.

There's a doc Ghosts of Abu Ghraib about the abuse n torture suffered by the inmates thats a bit hard hitting, but mainly just because you know this shit really went down.

Oh & The Rock.

i forgot about Riki Oh: The Story of Ricky. Plenty of OTT gore including this guy who uses his own intestines to try to strangle our hero.

https://personafication.files.wordpress.com/2014/02/rikioh.jpg?w=640&h=372&crop=1

it is just that, very much a comedy

That's the one written by and/or featuring Nick Cave isn't it? One of those films added to the watchlist ages ago, then forgotten and overtaken by other future watches. need to get back on the hunt for this one, cheers for reccing it to ice, nice reminder