Wanting feedback from TENS users

I am a university student looking at making a TENS machine. The machine I will be making is a belt wrapped around the waist and pads attached to the belt to be freely placed on the body. I have some questions that would help with the design process, any answers would be greatly appreciated and helpful.

When using a TENS machine where did you place the display screen when sitting down and walking?

Did you ever find the placement of the display screen a nuisance and if so why?

How comfortable did you find the pads and wires connecting the pads when in use?

Are there any comments you would like to make about a TENS machine worn like a belt?

Are there any additional comments you would like to make?