Sorry for the delayed response!
So the makerbeam works pretty well for DIY case rails, and actually you can build the entire case structure out of the stuff if you want using their system.
I got these rails and cut them to size:
And attached them to the inside walls of my case with the cheap hardware store equivalent of these:
And (this is the kinda weird part) I used this fastening system to attach modules:
Basically, they are sliding bolts rather than sliding nuts like in vector style systems. It’s a bit strange, but it works very well with both eurorack and serge LW/RS/DIY modules.
There is the following solution, but at $15 for 25pcs they’re expensive and really start to eat into any savings you get Vs using vector rails.
Final note: Makerbeam lacks the rigidity of burly vector rail so for longer spans it will flex a bit when you’re patching. My case is about 128hp and it’s pretty noticeable. Not the end of the world, but a small bummer. Shorter spans (84-ish hp) will be solid.