Aren't opinions wonderful things?
Just to be clear, I've got no beef with L/W or AA.
As far as taking it to the steel producer, I'm of the belief that nearly every one of the 'premium' manufacturers are using either Crucible or Carpenter barrel steel now.
Anybody who has been involved in any large scale manufacturing event has undoubtedly experienced tolerance stack up. While "in-spec", when everything leans towards the tight end, or leans towards the loose end, sometimes things just don't exactly work the way it was planned.
While this can certainly be an issue with a total "in-house" build, it becomes progressively more of an issue when parts of the build are contracted out. At this point, if the part is in "spec", the contractor is largely off the hook.
I noticed awhile back, with interest, the Beowulf case gauges you're selling. They look nicer than Wilson's, the knurling is a good touch.
Lets just say for a moment, that you're building these yourself(maybe you aren't, I have no idea).
You order the stock, lets say we're using 12L14 for easy machinability(I think that is what Wilson is using). You take them in your garage, lop them off in 4" sections on your bandsaw. Cut the O.D. Knurl. Center drill/ream to .5 on your lathe. Face. Run the reamer in until the go is even with your facing cut, then keep going X (lets just say .005 for the sake of argument) amount. Cut again to rough length on the band saw, or parting tool on the lathe. Flip it around in the lathe and face to desired OAL length. Stand it up on a surface grinder, or possibly a mill and take your cut down the middle for the minimum headspace measurement. Polish/Deburr, make look pretty. Package and ship.
Ok. Now lets contract this out, and for entertainment purposes, lets say we're making enough of these to contract out each and every step to a different contractor. How tight of tolerances can you afford to pay for in each step? .001? .0005? .005? Are your instructions good enough that the contractor who chucks up the drilled stock to ream knows they have to indicate the bore and center the headstock to make sure your chamber isn't as loose as a goose? Are your tolerances tight enough from the supplier beforehand that the next supplier doesn't have to go through the process again with each and every piece? Now think of the purpose you are selling these gauges for...how much tolerance stackup is acceptable? .003 will likely use up half your available headspacing range. Now what happens if the first supplier decides that 12L14 was a little too expensive this week, and decides to feed you some scrap 1018/4140, etc. they had laying around?
When available, I'll always take the part made in its entirety by one entity. Satern must be doing something right if AA licensed them.