Lancaster-

When I refer to the magtech as cheap and (have I said weak?) weak, It's not necessarily language against the product.
I actually like the fact that the product is thin. I get a better chance at good gas seal with it than with thick brass and that's what I like about it.
Cheap is good too. I can screw with it quite a bit and not worry so much about the price.

The 16b gun I speak of most is the Mahillon. It is uncommon in many ways (all of them are though, aren't they!), and I am perfectly comfortable with that.
With the chambers for the old 16b Gastight paper cases, I find the section of the new magtech brass small in diameter for the chamber at the throat, yet still too big inside diameter for the roundball.
Fireform then line with wax paper tube is the way, flexible for gas seal, and ok to hold the roundball.
I haven't shot this version enough to tell how many times I can fire each case before re-work.
The good news is that the re-work is cheap and easy.

I successfully conceived and pushed a campaign with many american 16b shotgun enthusiasts and an importer to get Cheddite (who was not very excited about the idea) to make a fresh run of 16b paper shotgun hulls and ship them to the US.
I ended up with some of these and intend to modify some of them for pinfire service, then to run them in my rifles and see how they perform.
The pair of Eley Gastight cases I got with my rifle had very thin metal sheet reinforcement inside the paper case walls.
I plan to do something similar with these before I run them in my rifles.
Just haven't done it yet. Swaging the rims down to fit my chambers is the last step in the process.
I haven't made tooling for that step yet.

Every step with these neat old rifles is full of discovery, very much like the way they themselves were steps along the path of discovery in the development of the breech-loading sporting guns and rifles!

--Tinker