Hey @boota,
A few things to consider, and putting aside the 48vs96 debate as requested:
Regarding the build – the AB168 and DX168 use the same metalwork 🙂
The DX168 uses dLive preamps – the analogue circuitry and conversion is of a higher level than the GLD/Qu AB168.
You mention maybe 3 stageboxes. If using AB168’s this would be possible with the addition of an SLink option card and an extra Cat5e run. With DX168’s you would add a DX Hub at the stage end to achieve this.
If you don’t need drops and plan to have all I/O in the same place, you could also check out the GX4816, this has the same technology as the DX168’s but in a 48×16 single 5U box.
This document may be useful – (https://www.allen-heath.com/media/SLinkConnections_V1_4_0.pdf)
I will let others chime in about their experiences on tangible differences in sonic quality.
Cheers!
Keith.