i've actually had the pleasure of owning both the 501 subdial futurematic and a silver cased harwood.
first the futurematic. great watch in very poor condition with wear to the Gold plated case and rough dial. movement worked fine, but i sold it mainly due to its condition.
now the harwood. as you said Nicolas, not the most reliable watch in the world, very difficult to set the dot in the hole so that it would actually work, if you took it off and blinked it would stop due to a pathetic power reserve, very small as was the custom in the day making it not practical for modern use. i only really bought it because it was the 'First auto'. the experience was not a great one, more a short and frustrating one.
i dont regret buying either of them as you need to experience these things and i dont regret selling them either. just a part of lifes rich tapestry.
enjoy it mon ami
Graham