It hasn't been out long enough.
However, it is just a SRD762TI that has been cut down a bit. Should perform very close the to regular QD version. Plenty of info out there on them.
And after reviewing that data it basically boils down to this between the Sig and DA:
The Sig will be quieter with lower pressure rounds, especially .300blk subs by several db.
The Nomad will be quieter with higher pressure rounds like .308, and you can probably split the difference with 5.56.
The Nomad has a much better QD system, and can swap between QD and direct thread.
The Nomad interchangable end caps that can use the E-brake to knock more db and recoil off, or flash hider end caps which work very well.
All in all I think it is pretty clear which to choose. Unless you are only planning on using it for .300blk subs the Nomad is a better buy.