Anything I should look out for beyond the usual wall thickness, proof, tightness etc caveats?
There is one thing I'd suggest you consider based on the two I have. There is very little metal in the action bar due to being a single barrel. And the steel in these is usually pretty soft. As a result heavy loads can stretch the action easier than on a double. My little 16 has been particularly suseptible to this problem so I'm holding my loads to no more than 7/8 oz. But it's old.....(even older than me--Whew!)