It sounds good, I installed it on my Yamaha 01v96i, to add 4 additional balanced outputs, which I can use for monitoring, or to send separate channels (when we play gigs, we send separate signals to the FoH engineer as we use the 01v96i for stage mixing and signal processing/effects).
DO NOT send +48V phantom power to these outputs (e.g. when feeding them into another mixing console): at first, everything works fine, but after 30mins to 1hour you'll start getting loud noise and hum. If you experience such thing, just switch off the phantom power for those channels on the second mixer.
Anyway, a good unit, very useful for live concerts as either stage or FoH mixing.