Battery nirvana

So it appears that there are a number of components running on batteries to choose from.
What battery operated units are you familiar with and would say are SOTA and better than ac line units.
I use a PurePower 700, it's a power regenerator with battery back up. The difference this thing made in my system was HUGE!
SOTA units, sorry, dunno. At the top of their price point units: I know one. The Apogee Mini-DAC runs off a battery and sounds very good indeed that way.
Any comments on dartzeel or asr?