Primaluna EVO 100 Tube DAC has anyone heard it??

As part of the new EVO series Primaluna has come out w/an all tube DAC. Cost is $2999 and it weighs around 29 lbs. It also has a tube based clock. Never heard of that type of clock. Can someone explain what that is. The DAC itself is based on a Burr-Brown chip set.
I'd also be curious on people's thoughts on what you might gain from an all-tube DAC that you wouldn't necessarily get by running a digital DAC through an all-tube preamp.  
I find one of the selling points strange. Primaluna claims their DAC weigh's 29 lbs. compared to most DAC's that weigh less than 10 lbs. IMHO I don't think you can correlate quality w/weight in a DAC. My RME ADI-2 DAC weighs in about 2-3 lbs. Does that mean it sucks??