Worth gettic a DAC with setup?

The Ayre QB9 DSD DAC and that way you can play hybrid SACD's from your computer! I'd also recommend the Audirvana Plus transport App for any DAC but especially for a DAC that offers DSD playback. Audirvana Plus can be found easily via the world wide web at http://audirvana.com

-
You have a very nice system, especially for someone who describes themselves as a newbie. The answer to your question is pretty straightforward but neither easy nor inexpensive to answer.

The Oppo 95 is very well regarded as an audio source and clearly has a decent internal DAC. Whether an external DAC would improve what you're hearing depends on a lot of things, but mostly on what you prefer with your gear. The competition among DACs at the level of the one in your Oppo is pretty fierce and you'll never get agreement here about which one you should buy.

My advice, which is free and worth exactly what you're paying for it, is that if you have the funds to experiment and the time to do some research, buy a used, well reviewed external DAC that seems interesting to you and hear what you hear.

If you're careful about what you buy and what you pay you can often have an extended audition for not much more than the shipping cost. That may be a little more complicated for you since I'm assuming you're in Scandinavia but I don't know of any better answer to your question.
-