I have a maple slaydawg and for my experience the translucent part is less durable than the white paint on the scope. The paint is chipping around the bevel but still plays very well so overall I'm pretty happy with it.
I had posted awhile back in FKC about my nihon ash lol clear badly flaking during the first day of owning it (and I don't play too hard or anything) and how I was bummed about it and rolf straight up bashed me for for talking negatively about the product. I was like yo, just trying to see if other people have the same issue!
Here's a picture of my ash slaydawg after a week or so of light use, the tama is quite a bit heavier than my others so it might be that? (90ish g) The clear bit is fine but the white bit chips, but it's stopped chipping as much now.
I bought that fish mod 2 months ago along with a bray mod a little bit after those came out. It's not old, the glued spike just destroys that kinda paint. They still slay hard tho. No complaints here I just won't glue the spike on my next one.
From my experience with kendamas, paint chips a lot more depending on the density of the wood you are playing, and the paint that is on that wood. Typically glossy paints chip a lot more with less dense woods, while matte is the opposite. Is your thorkild mod really light? this could be the case.
In terms of wood density, ash is usually less dense than maple and the six-year birthday and 3D Don are both Maple and the thorkild promodel and nihon ash are both ash so that would explain why the first two didn't chip much and second two chipped a lot. I'm not sure about the Fisher promod though
Along with many others, I find that gluing a spike sometimes doesn't play well with some paints. But on the otherhand, my tama's generally live longer than my ken's. So with this in mind I still glue my spikes to offset that spike wear. But what Iv found to help the two play together well, is to sand down the glued spike once it's dried, that way it becomes solid but smooth, and all those harsh & harmful sharp bits of glue become non issues. I use a glass file & it works wonders! ENJOY!