TotalDAC D1 Driver-anyone using one yet?

From what I have read, the Totaldac d1-driver appears to be a high quality buffer amplifier. I use a unity gain (i.e., x1) buffer by SMc Audio between my DAC and my amplifiers. My DAC outputs to a passive volume control then to the buffer then to the amps.

A buffer generally has high input impedance and low output impedance to reduce/eliminate impedance mismatches and cable colorations. Even operated as a unity gain unit, a good buffer can help maintain dynamics and tonal density thereby improving the sound of DAC direct-to-amp set-ups (i.e., volume control in the DAC) and systems using passive volume controls. Based on the available reviews and pictures, the d1-driver appears to be well-made and, if I wasn’t already accommodated by the SMc unit, I would certainly give it a try.

I have no experience with ARC preamps so don't know what substituting the Townshend Allegri Reference passive in place of my ARC REF 10 will do to the sound of your system.  I believe the Townshend is an auto former or auto transformer preamp so do your homework on the collective sound of those types of units and in general expect maybe a bit more detail and maybe less color and body compared to your ARC preaamp, but that is a gross generalization based on comparing the many tubed preamps I have owned with other TVC or auto former type preamps I have had here, but without ever hearing a Townshend preamp, which I believe uses their fractal wire.  The Allegri Reference unit is pretty cool and was on my radar last year when I was looking for a passive volume control after switching DACs to one that does not have an internal volume control.  The TotalDAC D1 Driver would seem to be a good partner to the passive Allegri Reference if you like the sound of a preamp compared to the DAC direct to amp sound in your system.  Wouldn't it be great if we could try this stuff before buying it?

@georgehifi - I believe you are correct. The information on the totaldac website says:

-one-box stereo version: RCA inputs, RCA outputs + unbalanced XLR outputs
-two-box monobloc version: RCA inputs + XLR inputs, RCA outputs + balanced XLR outputs

The XLR outputs on the stereo version appear to be "convenience" outputs for those using XLR cables but not really carrying two symmetrically balanced/inverted signals.  Sounds like a single-ended piece that must be doubled up (mono version) if you want a true balanced circuit.

Based of the huge input impedance and low output impedance, the d1-driver should work very well as a buffer.  You can get it as a unity (0dB) gain version or with 10dB gain.  I would really like to hear the unity gain version and compare the sound of it with my SMc unit.
From the website:

-very easy input impedance: 1MegaOhm
-natural low output impedance plus added 40ohm pure resitor for a perfect interconnect impedance matching
-can drive anything above 100ohm without distorsion