I think my highly subjective criterion would be
Would I personally desire that as my own marker, would I prefer it to what I have?
That pneu-nasty came out nice! Those loaders make a good match. Doesn't look like you need to carry too much extra paint with the small bottle.
For the open class :
Definetely, first thing I'm looking is the uniqueness of the parts, and the marker. That shows a lot of work and efforts to