I don't neuter my boys that are just pets. They have never fought and I doubt that they would. They do still piddle when they run around, it's how they mark where they've been, and how to get back to certain spots. It's making a little map for them, so I don't mind it.

I wouldn't call it marking territory like a dog or cat, but it can be seen as such. I really haven't noticed any odor from letting them run around, but they dont get to do it 24/7. Just an hour a day to say hi.

If you want to neuter for safety reasons, my opinion is that if they are raised together and kept together, they won't have a problem. This is just my experience with my boys. Good luck!