Round tip. They vary the pressure/speed of moving the tip so the letters are thicker and thinner. Kind of a cool technique, they purposely vary the thickness rather than trying to keep them perfectly the same. Lots of examples on their website.
I'm thinking it's piped as well. Maybe one of those tips that looks like a rose tip, but all one width (like a thick line...sorry I'm not familiar on what the different tips are called!!) and piped in calligraphy style.