<human>: Can you condense the text into three sentences or less?

My 8 month old Australian Shepherd, [Benny] is getting neutered next Monday. I know it's healthier for the dog and all, but I'm having a hard time coming to terms with this so all advice/help would be appreciated!

I'm nervous about him being anesthetized due to the chance of esophageal strictures, him not waking up, etc.

He also has quite the personality. He doesn't exhibit "bad" behaviors that neutering fixes, such as marking things, aggressive toward other dogs, etc, but he does this endearing thing where he barks at me before he does any commands (I say sit, he looks at me, barks, and then sits down). My boyfriend's dog is terrified of the white "barking box" and Benny will bark at it as if he's telling the box to shut up because he's trying to bark. As annoying as it can be sometimes, I'd be upset if this aspect of his behavior went away after neutering.

We have also started agility classes, and he's doing SO well in them. I don't want him to lose his drive/energy in this respect either.
<bot>: I'm nervous about getting my dog fixed so shower me with success stories of your happy, energetic puppies after neutering.