For the 3-minute ones I used a Sakura Graphic black marker pen for lines first, followed by a 50% Copic extra-wide marker to knock in big shaded masses. The strong thick line of the Sakura pen acts as a good anchor for the study. I find those heavy lines very challenging to control in terms of any subtlety.
On the 5-minute ones I was using a Pitt medium black liner per, which has a responsive but much less emphatic line, plus the 10% and 30% extra-wide Copic warm gray markers plus a 50% and 70% warm gray brush tip to add modulation to darks.
The super-wide markers are good for filling large areas, but their straight-line chisel tip makes for sharp edges when ending marks, and they rapidly run low on ink over broad areas, giving a 'brushy' look I'm still learning to exploit.
A week after this session, I've modded the broad markers a bit, cutting the edge into a slight curve that should make for a broader range of marks.
I also initiated a fade test today, putting half of a Copic drawing into my window. I'l post every now and then on developments.
