Need integrated amp with built-in USB DAC

Assuming this a piece you'll want to keep for several years, as opposed to changing it in a couple of years, I would recommend along the lines of what Hgeifman posted above. DACs are not a mature technology and as such they are still evolving pretty fast. In two years you can expect current DACs to be surpassed by much. Amps are mature, on the other hand.

I suggest you look at iFi products for the DAC section. In fact, in their case it would be DAC and volume control. For $500 you get a good unit, and you can pair it with an amp of your liking for a grand.

Sorry I didn't see your question earlier.

What I mean is the sound quality you can buy today for say 2k will probably be available in 2 years time for 1k or less. Of course there will be a lot of exceptions and special cases, but that is what I observe.

Then there is the constant flow of digital formats. Up to now I don't care much for DSD but you may like something that comes down the road.

It doesn't mean something you buy today will not operate in two years or will sound bad, but rather in terms of bang for buck. In the last two years I have had, or have now, 5 DACs ranging from 3.5k (exaSound e22) to 0.2k (iFi) and have to say I've been impressed with how much better quality of sound you can afford for less money lately.

Regarding maturity of amps: you are right about class-D. I wouldn't say the same for ss or tubes, though. BTW, I just finished assembling a couple of Hypex UcD class-D monoblocks and think they sound very well for relatively little money vs my tubed McIntosh MC275. But I feel no urge to upgrade the MC275 or the Lamm pre for something newer. Maybe for something better, but in my mind newer doesn't equate to better in that class of equipment.

Of course these are my two cents and by no means I pretend to "be right" :-)
Just trying to watch after somebody else's wallet.

Cheers