Ballistic Nylon was named "Ballistic" because it is used in conjunction with Kevlar® or Spectra® to make bullet proof vests. Although it is extremely tough, it is not ballistic proof.
Any dual bladder design is suspect because it is adding more problems than what it is trying to solve.
Example: The second bladder is to provide backup in case of the primary bladder failure. It solves one problem (that can be solved by other means without extra gear) while adding many.
1&2. The second bladder requires a second power inflator, this is more prone to failure than the bladder, all it takes is some sand. It can fail on or off, so a runaway inflation or failure to work is possible.
3,4&5. A second LP hose w/connection to the 1st stage; another 3 failure points, the o-ring on both ends and the hose.
6. The possibility of task loading, which one do I use for inflation deflation??
There are more but you get the picture (hopefully).
The design(s) of the Halcyon wings are significantly different than the others. I have a few different brands and I will only buy the Halcyon wings in the future.
I must say that you have found the ideal use for the OMS wings.
omar