Opinions on Audio Research DAC 2

I like to hear your opinions about Audio Research DAC 2 solid-state DAC. Stereophile has a review on DAC 1 but this has a different chip set. DAC2 and DAC1-20 have Ultra Analog D20400A chip regarded as one of the best. This is a multibit R2R DAC. Specifically, I want to know low frequency performance below 100Hz and highs above 3 KHz of DAC2.

I have AR DAC3 which uses delta-sigma DAC from Crystal Semiconductors CS4328. My other digital source is Cary 303/200 cd player with Burr Brown PCM1704-J multibit DAC with HDCD chip PMD200. My Pioneer PD65 is mainly used as a transport.

My speakers are Thiel 3.6, VTL 2.5 preamp, and Mark Levinson 23.5 amp. My listening room is 16' x 22'. All vacuum tubes are NOS variety. I enjoy both vinyl and CDs and hence the bug to update!

Finally, any other DACs I should consider from more recent models.