Go for the Aurender. Some of the reasons why…
Aurender is a streamer only unit that utilizes a fairly large caching area and that helps with getting the signal as clean as possible out to the DAC; it has a USB output which means it will rely mostly on the processing inside the DAC; it has a lot more user friendly UI (Lumin is horrible in this regard)
Lumin D2 is a streamer with built in DAC that is why it only has spdif out. If you only need a streamer then get the N150