Tip size of paint markers

Can anyone tell me of what size the tip of paint markers is?
Are there differences between Tamiya and i.e. Testors markers?
I'd like to mark panel lines with this...
Is the acrylic paint from i.e. Tamiya markers the same as in the Tamiya X/XF bottles (water based), or is this like Tamiya spray cans (synthetic acrylic)?

Regards,
Steffen