The wadia is using the digital stream BUT...and here is the difference between the $300 and $2000; the wadia grabs the digital stream AFTER apple touches it i.e converts the raw feed from the drive to spdif...etc. MSB modifies the unit and grabs the digital stream DIRECTLY off the hdd before anything is done to it, then with there proprietatry tech they convert the signal to spdif and return a signal with a measured jitter of around 7ps. There is a big difference.
I only know this because I spoke at length today with MSB about this topic...i.e "how is that others are claiming to offer digital out the port with no mods having been performed".
I have decided to go for the ilink and connect it to my Meitner Bidat.