Thank you for your input William!
I think I'll get the FRI 19 channel headband. Based on yours and others advice I would likely strap the BCI board to the back of the head and use the 18 inch/45 cm cables along with a pair of ear clips. That would minimise the cable length as well as potential for movement. Only the battery would be worn in pocket which likely wouldn't affect noise.
If I understand you correctly, if I were to apply shielding of some sort even though it's not commonly used, I should connect it to OpenBCI Bias/Ground.
I would then apply an experimental shield and see if it makes any difference to a baseline noise measurement.
Is there any best practice with the OpenBCI for unused electrodes, should they be tied to reference or is it unnecessary regarding noise?
I'm also not quite sure how to measure just the noise component, without a body attached. I found this on measuring Self-Noise of OpenBCI. I want to measure the noise with the cables attached to the headband to measure the noise floor with and without shielding. Should I leave the electrodes open, short them to reference and ground, or with some series resistor to replace the body?