Am barely asking people who more knowledgeable about the brand and maybe this particular piece if there is any piece of information that i would have missed.
In my book that 5231J is not subject to any specific hype (as compared to a Nautilus or a Chronomètre Bleu) and has been produced in very limited quantities (maybe 100-150?) with very high-level of craftmanship… if some one could alreasy confirm whether i am in the right or weong, that would be pełny enough for me 
No need for a crystal ball about the market prices in details…