Advice for a usb dac

I would like to jump into PC Audio and looking for advice regarding a Dac (entry level). The components of my system are: Maggie Mg 12, Odyssey Stratos, Classe CP 35, Rotel cdp 991. I am thinking about the AudioQuest Dragonfly v1.2 OR the Cambridge Dac Magic 100. I don't want to invest to much for now. Not even sure about my setup: my pc is 25 feet away from my system, so I will have to use a long cable. Any advice or other suggestion/recommendation?