I know the OP is talking about fancier metal cases which would be cool if there were some nice ones.
I don't know if this would fit any of the mods out there or not but I noticed the other day that Innovapor has a pretty sturdy looking Pelican case for the EVOs and 510s for $25 w/ Lifetime warranty.
the lifetime warranty is a feature of pelican case...they have a bunch of different sizes..they can be had for alot cheaper too...
I think I need to find some size specs on a bunch of the mods like the chuck, xhaler, and Super Ts...and crank out a couple of custom hardened leather, neoprene lined carry cases just to see what people think