Any fraying of brush pens depends on 1) how much you use them (all brush pens will fray eventually with use) and 2) what paper you use them on. I love rhodia paper personally. These pens are still good for me and I use them occasionally. For someone using everyday all the time, i would give them no more than 6 months to a year. Like I said, it really depends on the person and also how heavy you press down on them.
taylorandcarolina if you are using the pens directly on the paper I recommend a bleed proof paper meant for alcohol markers (works for water soluble as well) and is the smoothest so will not fray your pens as fast as normal paper. I recommend transotype bleed proof alcohol marker paper but it’s pretty pricey. I like to also use Rhodia paper but it does depend on the type of project you are creating. Hope that helps!!
