I personally bulk load 'whatever I can get my hands on'. I have 2 bulk loaders on hand filled with a roll of something all the time. I typically keep color in one and BW in the other if possible.
My current faves are expired Kodak Portra 160NC and Ilford HP5+ 400 for mine, but usually I keep BW Arista EDU Ultra 100 and 400 in the two loaders and shoot color from pre-done cassettes. I just happened to score a bunch of rolls of the expired Portra 160NC so it's been living in my color loader lately.
Without derailing this thread, is this ORWO film something that requires special processing or can you process it in typical BW chemicals (D76 or Diafine) without any problems? I'd never heard of it and your shots above are lovely so I want to try it. I tried some Kodak of some kind in color that required some special steps and it was just too much for me to figure out so I gave up on it. (Does it have a wierd backing? Does it have sprockets?)