There is no way to use DX200 or 220 with DSD512.
This file is very high demanding of processing power and consumption power
The WM1Z is still very hard to beat if you use PCM and crave for that of a more analog style.
I had the DX200 as soon as it was out until last year I sold and got the SP1000M, and then the WM1Z - the main reason being the wireless DAC mode. I also had the Hugo2 around the same time. All the new DAPs now support the wireless DAC mode and I was already pretty happy with the DX200 from the SQ point of view and no reason to stay with a twice as expensive DAP. Modular design is also what sets it really apart and now the Nutube module. So, going back to what I was happy with already (except the software, but the Lurker FW is awesome to get around it).
Do you mean DX200 only supports the DSD512 in USB DAC mode but not as a file on the storage device? I never tried anything more than DSD128 on DX200.