I've owned both and prefer to TA-10. No wall wart power supplies, better quality(no scratchy sounds or uneven output) IC controlled volume control and more sampling rates are a few reasons. The gain on the TA-10 volume has a very slow progression, so expect volume settings in the 60+ range with many cans.
I own a lot of Schiit products and the Vali 2 is the only one I ever returned. Mine was simply a lemon. Every company has one from time to time.