My impression of the Serbu kaboom:
I'm convinced that at pressures that can be reasonably expected,the Serbu can stay together. That includes some serious over pressure loads.
Maybe thats enough.
But most modern firearms,when they do fail, fail in a way that seems engineered to protect the shooter as much as possible.
If the Serbu acheives catastrophic failure,that breech cap is likely to punch a hole in the shooter's head.
You pay your money and make your choice!.