You guys are braver than me. Yes, no doubt you get more for them that way. But have you never been burned when the supposed new edition failed to materialize? I read all the time people who post that they no longer have one of their favorite movies cause they sold it when they heard there was...
Although I've given a couple away, most of them I've kept for a doomsday scenario: my new dvd gets ruined or lost at some point, and the dvd is no longer available for purchase (or only in pan & scan), I can still watch the old dvd of the movie. Admittedly a pessimistic philosophy, and so unlike...