I laid eyes on all the Heuers, so I'm somewhat surprised by the strong result of the 2447NT. Recent auction results suggest to me that condition has been paramount, regardless of rarity.

My notes on that watch-
Case: strong lugs, but more polishing of the case sides evidenced by the soft line in the transition to the caseback at the 3 and 9
Dial: clean, free of tool marks, quality printing. Lume was unusual, almost opaque with a milky hue, maybe a tinge of green
Hands: similar lume in the H&M hands, chronograph hands were all repainted poorly. Sweep was incorrect (look at the wide tail)