Bigkidz, DHT designs can sound excellent but are they necessarily any better then other designs is up to the product's ultimate design topology, parts selection and synergy.
We have the Manly 300b preamp which is a superb DHT 300b based preamp, the CJ ET 5 and GAT creamed that preamp, now the CJ pieces were double to four times the price, but the GAT was far superior.
As per the Niagra 7000 it was aweful in our reference system compared to the Audio Magic Oracle, on a direct comparision the magic of the system went right out the window with the AQ, unit, and for your information we have tested most of the big power conditioners and the Audio Magic bested them all. Our other test units, Running Springs, Silver Circle, Audience, Isotek, in the past Synergistic and Shunyata.
As per the dac issue, personally it would be hard for us to recommend such an expensive dac no matter how stunning it sounds as Lampi does not have an upgrade path.
For a lot less you can get an Aqua Formula which is a 100% modular and upgradable and it is also a NOS dac, but with some very cool features, FPGA, ability to play DSD and high res PCM.
The new Formula with the revised anallog board is way better than the previous version which had a few sonic issues, the new Formula is really fantastic it may not be a melifourous as the DHT sounding Lampi but the Aqua line is known for musicallity,
Another possiblity trade in the amp, preamp, and get a Vinnie Rossi new DHT 300b hybrid amp/dac combo which has been wowing people at the recent CAP and New York Audio Show.
There are very few $30k ish dac's that we would recommend that unless the company offers 100% modular upgrade ability you will have spent a lot on a future boat anchor.
We don't sell MSB but their designs are modular, DCS not upgradable, Aqua 100% modular, these would be products we would look at.
Dave and Troy
Audio Doctor NJ Aqua Hifi Dealers