Yes to me it is better but not if you're strictly talking 'sound quality'. It's better because it offers me stuff I find useful that can't be found on the ODAC such as XLR-output, discreet volume control that's of a good enough quality so it can double as a pre-amp, the possibility to hardware-set pre-gain on a number of levels, hardware control of oversampling between x1,2,3,4, 'best' (depending on input) or to switch it off entirely.
For the DAC: both use the Tenor USB-implementation , the differences are in the DAC-chipset proper (iirc ES9023 for the ODAC and the PCM1792 for the V800) but especially in the way the signal is treated post-processing (filtering and conditioning etc). They do have a slightly different 'signature' and I prefer what the V800 offers but of course you need to keep in mind that that 'signature' is not just created by the DAC-chip (frankly I don't believe there to be much if any difference there, certainly not audible) but mainly by what happens to the signal next, the OPA's used in the DAC's amplification stage etc.
I would have to agree with this, when I say DAC, I mean the implemention. Likely it's not the chip, but the implemention of the output stage is what makes the big different. I believe the DAC chips have schematic inside with amps inside, and that could possibly make crucial changes to the signal also.