When the detail has started to 'soften' on the mouldings, ie. 'looks melted', it's a pretty sure sign that the mould has aged. I worked in the injection moulding industry for about four years...I'm no expert but I have a little knowledge (which is a dangerous thing I'm told
). It is a shame too because, as you said, there are many things other manufacturers haven't covered. I've waited thirty years for a 1/48 Handley Page Hampden and finally somebody has done it.
Anyway, here's the latest fe pics of my Panzer IV which I've been quietly stealing an hour here or half an hour there to work on. Progress hasn't been huge but I'm experimenting with filters at the moment so the time frames suit me. I'll apply a filter to the model which takes around an hour. Then I let it dry for 23 hours...works for me. As you see it now, I think it has about nine filters in light grey, dark grey, dark earth and sand. The effect is very subtle. I hope the pics show what I want them to. So far, the filters are the only weathering I've applied.
Peace.
PzIVPainting1.jpg
PzIVPainting3.jpg
PzIVPainting4.jpg