Euthanizing DVR shows...

I have a bunch of shows marked "Manually Delete" on my DVR. Most of them I've already watched and need to clear off to make room for more content. As I was going through the shows, I was presented with "Erase Now" or "Erase when space is needed." Of course, more space is need so either option means it the show will get deleted almost immediately. However, it just seems more dignified to select the "Erase when space is needed" option and let the DVR erase the show...