First of all, thanks for providing specific questions since open ended stuff tend to get lots of junk suggestions. From my painting experience, I personally would recommend the CR over the BCR for reasons as following: BCR being siphon-feed require you to operate at a higher pressure, though the larger paint storage will allow for larger area painting, you will be losing the better details sprayed at lower pressure the CR would bring you. Detail painting would be rather important if you do German aircrafts with mottles for camo which you can't really mask easily. At the same time, the paint cup on the CR actually holds a lot of paint and will be able to cover a full body on a 1/48 WWII fighter. Though the BCR allows you to change the paint on the fly, I don't see what the point is for scale modeling, since you have to wait for the current layer of paint to dry to go on the next anyways. The siphon tube itself is relatively more annoying to clean as opposed to the paint cup on the CR, which you just pour the paint out and wipe with a towel and you are already 80% done. I mix my paint in separate jars I bought from Pearl art supply store for like under 80 cents so the paint color consistency is still there.
Another suggestion for the airbrush choice is that if you do enamel paints from say ModelMaster lines, it might be better to get a HP-CS from the eclipse series due to the self-centering nozzle actually make cleaning a slightly easier chore, yet still fine enough to do most work on a 1/48 aircraft and basic camo for 1/72 scale.