I was using an Oppo 93 from silver disc or hard drive, then I evolved to JRiver ROHQ, first with Intel integrated graphics then with a pretty good AMD 970 graphics card. I would say the Oppo and ROHQ/Intel were comparable. ROHQ/AMD is somewhat better. I can still play silver discs from the BD player in the PC with AnyDVD HD. So, the Oppo is in the bedroom.
A big issue is that via JRiver you lose access to the menu on the BD, including chapter titles and selection based on that. Tagging those BDs in JRiver yourself can be done using Particles, but that looks difficult and I have not done it. So, mine is very clumsy right now. A friend with a 103 cannot stand that, so he keeps his videos on hard drive via USB using the Oppo GUI which gives him access to the disc menu. He has a big music library on his NAS, but does not use the NAS for his video library because the Oppo cannot access it. He has not had success with DLNA. Music from JRiver as player goes straight from the PC to his prepro via HDMI, not through the Oppo.
Not sure how it might work out for you. If using the Oppo as your DAC, you could play FLAC, etc. with JRiver as the player(gapless) and feed it to the Oppo via HDMI (stereo or Mch).
Also, you could consider TV via JRiver and out to the Oppo via HDMI. That could eliminate your cable/sat box and monthly fees. I use HD Homerun Prime for that.
As I am sure you know, the 105 would be a better DAC than the 103. And, I like Darbee in my setup, so I would recommend the 105D.