I had the factory custom version, the CX500C. Loved it. I'd have another tomorrow.
Leaving aside the early camchain problems, what puzzles me about the original 1978 CX is how the designers could stand back, look at it and think... "Yes. That's exactly the design that Joe Public would want." It got some rotten-to-lukewarm reviews from the trade press, and these were probably based on its appearance.
The CX was possibly ten years ahead of its time, and it deserved to sell well... but how many more would Honda have shifted had it been, well, prettier?