I can't recommend any as I don't own any of them, but I'll try to help guide you in your search for an answer.
I think out of the ones you have listed, the Audio-GD is one of the more popular DAC's that a lot of people here own, and you should definitely read through the official thread on it: http://www.head-fi.org/t/624517/audio-gd-nfb-11-32-delivery-impression-thread
Being both concerned with audio performance AND build quality, the NAD is one that I have been eyeing myself, that I'll probably get around to purchasing eventually. It's not as well reviewed here but there are a lot of outside reviews on it. They have collected a lot of them on the official product page, so check those out here: http://nadelectronics.com/products/digital-music/D-3020-Hybrid-Digital-Amplifier#heading-reviews
The Teac is another one that caught my eye because of its gorgeous design and other components in the same product line that all look beautiful together, although after reading some reviews, it seems like the actual audio performance doesn't rank as high as others. That isn't to say that it gets BAD reviews, just that it doesn't seem to be as good in terms of audio performance as others in its class / price range.