nice discussion going here, and I am happy to jump in with a couple of observations.

The one you are evaluating (shown on top) bears a close resemblance to one of the ones that we show, in our comparison page (shown on bottom). Both have the same hands; blue-registers-on-blue-dial; painted markers (rather than applied). I had previuosly questioned the authenticity of (a) the blue-on-blue and (b) these hands, but was told that TAG-Heuer had authenticated the one shown below.

My main question regarding the one on top is about the lettering -- Heuer and Monaco. The Monaco looks BIG and the Heuer looks small. The three needles on the registers also seem to be mismatched.

This is a tough one to unravel. I would want to have a very close look at the paint on the dial, the luminous dots, the markers, etc.

good luck and thanks for posting here.

Jeff