After a break, and seizing the painting opportunity offered by a sunny, calm day- I found time to try out my new Harder and Steenbeck airbrush on the Comet. The paint used was MIG SCC15.
That's the British Olive Drab used between 1944-45; a shade that's quite a bit darker than the US Olive Drab used on the Sherman, and other armoured vehicles.

The 17ml bottles on the bottom row are SCC15. I used a
whole bottle on the Comet (undiluted), and another on the Cromwell.

It didn't seem excessive. Then again, the paint went on very easily using a 0.4mm
needle in The H & S Ultra (it was also supplied with a 0.2mm needle for finer work). The airbrush provided a smooth and even flow.
Here's my compressor:

and here's the Comet, as I left it, in Covid-free December 2019. Here it's sporting US Olive Drab; but this was only intended as a convenient stopgap colour. Covenient, that is, because it came out of a rattlecan.

Here we are after just one coat:

...and not forgetting the turret:

If you want a direct visual comparison of the US and British flavours of Olive Drab, here's the Comet hull after a light pass with Brit Olive. Below, you can see the much lighter US Drab still present on the wheels.

After a couple of coats, the Comet's colour is finally beginning to look familiar... distinctly British, that is.
Apart from a few cosmetic niggles to sort out ('welding' seam on rurret roof), and some light weathering- I'm happy with the colour. A touch of 'wear and tear', and some decals should make the tank fairly presentable. Next, I'll have to sort out the recoil and elevation.
Here's a pic of the Cromwell, I also painted this afternoon. The distictive Brit colour is more apparent on it, I think.

Ignore the gaps in the bodywork, The upper hull is not fully seated on the lower hull- that's just to allow paint to fill grooves and lines.
Other pics of the Cromwell will be posted on its own thread.
"Get your facts first, and then you can distort them as much as you please"- Mark Twain.