I think opinion here is probably divided about equally betwewn ontheecuttingedge's Ziggy brain and vonsmith's XTF1.2. The Ziggy brain has a lot more knowledge built in, but discards most of Hal's assistant functions. The XTF brain is more compatible with the other features of the Hal assistant, but by comparison has very little built-in knowledge. Each, in their own way, is optimized for learning. The default brain-subject to re-evaluation after Robert releases the update patch-takes third place behind either of those user-created brains in popularity, and the primary virtue(?) of the uncensored brain seems to be that it's learned to talk really dirty from exposure to the general public.