Exactly Bernard ! I do acknowledge a 'break-in' period and as several of my "EE" friends have said, capacitors 'set' themselves in a relatively short time, no where near 500 hrs !!
Neil, I have read and heard the wire insulation break-in you mention and while I agree, again not 500 hrs !!
This isn't the first time I've seen the magic '500' hr break-in number discussed. I firmly believe that it is nothing more than a BS / Marketing ploy so as you become accustomed to the piece your 'breaking in' !!