I have a Case backhoe so I can't speak to any of the Deere bucket setups. I have a 24" bucket that stays on the backhoe for about 90% of what I need to do. it is about the perfect size for ditches, general digging, and pulling trees and rocks out. I also bought a 12" bucket last year for a long ditch project (600' in rock and clay) I also had a rented ride on trencher because I was only burying 2" conduit and 1" water line. The trencher did about 40% of the work, but I had to get the backhoe to get through a lot of rock. the 12" bucket was overkill, but I think it is the smallest you can get for a full size hoe. It did pack off with clay and after a while, i quite trying to clean it out and just used it to "peel" back the clay. The 12" bucket I bought was a Case OEM bucket that still had yellow paint on it. I paid $500 for it and he threw in about 6 extra teeth and included the top pin. As I understand it, on 580/590's the 12" bucket takes a different top pin. All other bucket sizes are fully interchangeable.