R2R Ladder DACs or All in One Streamer Solutions


I am soon to own a Pass INT 25 integrated amp. I also own an Oppo 205. 

I am now searching for a separate DAC to replace/improve the DAC in the Oppo.
Budget $2k. Used preferred.

I like the R2R ladder sound and want a tube inside for a little balance with the Solid State gear.
My current source is the Oppo 205.

I am also shopping for a Streamer/Ripper/Storage device. Roon friendly and DSD capable.
Budget also $2k. Used Preferred.

It seems that the few offerings of these all in one solutions all contain a DAC.
My thought is that the DAC included will not be any better than the Oppo so it is of little use.

Has anyone been down this road lately? 

Am I missing something?

Thanks in advance for sharing your experiences!
chorus
The owner of MHDT, Jiun, reportedly started buying up as many of these chips as possible and they became the foundation of an enormously popular model of DAC. Clearly it's not "functionally obsolete." You can read around to see others on this chip. A classic car does not get "trounced" by a modern piece of junk. Indeed, it becomes "classic" not just because people are sentimental but because of design. That's why the reference to Frank Lloyd Wright is in my post, too. I can explain it to you, but I can't understand it for you. Over and out.
At this point I recommend one with volume control as you request. A big rotary pot with level indicator display.. All play apps have software (remote) volume ctrl. It also includes 4 digital inputs for source pass through selection, headphone amp and DSP with calibrated mic. mini DSP SHD Studio. I power one with an UltraCap 1.2 but a Teddy Pardo would be a fine choice instead down the road. I will say that the 1.2  @  12 volts runs 140°  and I put a AC Infinity mini fan on it.
I still believe that a cheap Topping DAC will exceed the Oppo but if you want a sweet spot look at a RME ADI-2 DAC.
It has EQ, a remote and enough features to keep you busy for months.
These are just suggestions, good luck finding a perfect fit.
I bought my MHDT Labs Orchid because I'm all about the flavor of the month.  I could care less how it sounds, I just want to be one of the cool kids.  So yeah, I got rid of my Auralic Vega (much newer and a lot more features, but no cool factor) and kept the Orchid.  What are these chip things you guys are talking about anyways?  My Orchid runs on NOS, like my Honda Accord.
Dacs are probably the least important part of the reconstruction chain. Any modern 24 or 32 bit DS dac implemented by a competent design team is all you need. Actually I haven’t the faintest idea what DAC chip I’m using other than I know it’s DS and frankly don’t care. I hear no distortion or noise in the quiet parts of classical music nor the banging of rock. R2R chips can be implemented to be indistinguishable from mediocre newer chips and I doubt I could hear a difference but it seems that isn’t the goal of these types of DACs they want a sound signature not a transparent reproduction of the source. To answer the OP question get a all in one and quit worrying about what DAC chip it has.