Streamer with built in DAC...is there much difference between brands?

I have tried streamers from $300 (I have a Bluesound Node) in relatively small increments all the way to $22k (I have a Aurender W20SE) and each increment has been worth it (finding the best at each price level). But as @soix says, it depends on the rest of your system. 

By the way, just for fun I did connect the Bluesound Node to my $17K DAC, $22K preamp and $38K amp. It sounded pretty good.... but not like my $22K streamer. 

An optimal compliment has occurred in my systems where the investment in Streamer = DAC = Preamp = Amp. Not cast in concrete... but I wouldn’t be looking for a $10K streamer with a $500 DAC... but I surely would not be looking at a $500 Streamer if you have a $10K DAC. It’s easy to dismiss the value of a streamer... so you should be looking in the same neighborhood as your DAC. 

We have come a long way since the phonograph.  It’s hard to find a bad sounding streamer/DAC these days, but if one does the homework, it becomes clear there are many variations in features, technical execution and specifics of the resulting sound.  A lot comes down to personal preference, including how much to spend.

Understood on the rest of the system but is something like a WiiM Ultra with a $500ish new/used external DAC (Topping D90?) going to be a better option than an $800ish Eversolo DMP-A6 Gen 2 using the built-in DAC?

@asahitoro my guess in that particular case like most it will come down mainly to personal preference.  Features matter as does details of the resulting sound in a specific system/setup.  Each case is unique. 

Understood on the rest of the system but is something like a WiiM Ultra with a $500ish new/used external DAC (Topping D90?) going to be a better option than an $800ish Eversolo DMP-A6 Gen 2 using the built-in DAC?

@asahitoro  A big benefit of separates is you can sell/upgrade each unit individually, and it just offers more flexibility of choices in general.