So far so good. It doesn't clog at all for me. Obviously the white out will harden on the tip of the marker, hence the PRESS-NO-GO valve system, just press down lightly and it gets the crispy stuff off and it's ready to go. I have been using these to highlight slappies and for rough rusty surfaces. Works great on bumpy stuff. I really want to try this with garvey/marsh mix. Would be cool if AP made a pre-mix garvey/marsh for those of us that can't afford $40 bucks on 4oz garvey. Only reason I am not rating this 5 is because the refill cap is super hard to unscrew compared to pilot pens, probably cause it's plastic.
I bought a black one of these awhile back, when i first tried it out i was not a fan. The thing streaked like crazy so it ended up sitting on my desk looking neat. Recently i decided to take the thing out and see i i could get it writing well, i hit some signs and newspaper machines and then abused it a little on some raw wood, now this thing kills, its also perfect size to take everywhere! I think the nib was simply a little to stiff or dense out of the box to flow well so if you get a streaky one just work the nib a little and it might fix it. I was also a little worried about the glass body but ive dropped mine 10+ feet onto to concrete and the dam thing literally bounced and it didnt even chip the glass so i think these might be borosilicate glass (pyrex/pipe glass) Also the black magic ink plays nice with black pilot if you prefer that refill, but the marker will drip on the first couple tags if you really fill it good, mixing magic ink and pilot also seems to be a good way to stay nice and opaque and shiny and still give the buff man a bad day.
THIS MARKER IS SEX. I copped the silver, and it's one of my favorite makers at the moment. Never streaks, the silver is bright and highly reflective, and the flow is amazing, ESPECIALLY if you flare out the nib. If you don't know how to do that, take out the nib before you start pumping, put the chisel tip inside, and rub it on some rough concrete until its nice and puffy. Drips for dayyyys. This ones a must-have.