Close to bombproof.

Picture this scene:
Three shrieking children with a spraying hose and a skateboard. One corgi going apeshit with a really loud plastic soda bottle. All within ten feet of me while I was picking one of Solomon's back hooves. After I put his hoof down he turned a bit so that he could keep an eye on the hose because he hates getting his head wet, but other than that he didn't react at all, not so much as an ear pin or a twitch.
Oh yes, I asked the children to please move because I did not particularly want to be kicked in the head should anything startle him. I think I did a good job, because the children were solemn about it but not upset, and they said "okay, hey, let's go play over there!" and skateboarded off, crazy corgi in their wake.
I'm getting better at picking out rocks. They can get pretty deep in there, but he's a really good boy and while it's a little hard to get him to pick up his hoof initially, he holds very still once you have it in hand. I'm guessing it'll get easier to pick his feet up as we build more trust.
He had some large loose flakes of skin on the bottom of his feet. The BO (That's Barn Owner, for the folks on my LJ who were asking) said it was normal and to let it come off on it's own.
Today I was going to just give him some treats, but the arena was empty and nature abhors a vacuum as much as I don't like the thought of a horse not getting to walk around. He wouldn't go faster than a walk for me, but was otherwise good.
I do notice that he does lose some of the food that he chews. When he eats carrots he ends up with minced carrot bits in the bottom, which he then licks up. I'm not sure if that means he really needs to have his teeth floated or if he's just a messy eater. He probably does though. I wish I could do it for him.
He did get walkies, carrots, brushing, and hugs though. His eyes seem brighter these days. And Tuesdays he's my hoss. :D