I have the hifimediy DAC built on ES9023:
It's great, and I use it to drive all my headphones directly - FIIO E17 and FIIO E6 are now unemployed.
The sound has great detail over the entire frequency range, solid bass impact and huge soundstage.
ODAC is supposed to be an affordable reference-level DAC, but it uses the same ES9023 chip and costs over 3 times more.
I am sure that it has better specifications then the hifimediy DAC, but are there any audible differences?
Can ODAC drive the headphones directly as well as hifimediy does, or does it require an amplifier?