Good to know that Russ keeps an eye on me and agrees, but only to a point
Humbrol is and was my favourite but the quality HAS slid since the late eighties. One thing I believe they changed was the amount of pigment (paint = pigment/coloured stuff + glue).
Only pigment = dust
Only glue = clear laquer
What I think they did was to reduce the size of the individual grains of pigment, which is a good thing, BUT they didn't increase the number of grains to make up for the loss of total volume. The result was a "finer" paint with reduced coverage. This hit the light colours most. My solution was to take two jars of the new "formula", pour of the "clear" stuff into a small tin, dig out the lumps of pigment from one jar and stick it in the other and then fill up the rest of the jar with the "clear" stuff. This gave me better coverage.
I bought a lot of tins back then and they are still around since family life has reduced the building and painting to almost nothing.
Tru-Color paint: I am testing a "dark yellow" railroad bottle on a Pz III (still assembling plastic) but I am happy so far.
I would be very surprised if they changed the chemistry when they make armour/aircraft/naval paints.
Robin, not keeping an eye on you, I'm just agreeing that we see "eye to eye" on some of the same ideas regarding model building. For me, I think that's fantastic given that we're live on different continents! And it proves what a great modeling tool this internet really is. When we share ideas, it's better for the hobby as a whole. In my youth, I never would have been able to talk with others across oceans about the hobby I enjoy, all the more reason that when others tell me model building is dead, I disagree with them and point to this site and others. Model building isn't dead-- it's now enjoying a whole new level that we never could reach at the local drugstore or five and dime. Accuracy, artistry and community in model building are so much more advanced today than they ever have been. I still like my LHS, but even they are still in business because of the Internet to some degree. As for paint-- I believe enamels will remain the least trouble and the most effective paints for modelers. They have limits to be sure, but so do the acrylics-- my solution is to find out what works for you and go from there.
As for Humbrol, I worked in an LHS for a while before the owner passed away and the estate manager mis-managed it, and then sold it for a fraction of what it was worth. We carried Humbrol as one of the product lines, and having experienced the quality of Humbrol in the 60s as a youth, I bought twenty or thirty tins. I found they would not dry completely at all. I discovered this the hard way, after painting two Hobbycraft Sopwith camels with Humbrol "Bronze Green". The paint remained slightly tacky and "cold" to the touch for weeks (good thing I'm a slow builder). I ended up stripping it all off. Thinking it was me (hobby paint issues are usually more because of operator headspace than the product), I repainted painted another project with Lemon Yellow. Same thing happened. I then painted a strip of Evergreen with about twelve different colors as a test-- every one was the same. That strip did not dry for over a month. So something in the formulation was off. This can happen with batches of paint to any manufacturer, but not usually over twelve different colors-- so something is definitely off with Humbrol.