The main difference between a 0.1mm tech pen and a Sailor Saibi Togi is the consistency of line width. A tech pen will give you the same line consistently. With a Saibi-Togi nib, a change in angle, pressure, or nib direction changes the line.
Did I like the experience? Yes, I did. It felt more organic, more in the moment. The nib translated my pulse, my breath, my state of mind, onto the paper.