Just this weekend my brother counted the DVDs Ive given him over the past 2 or 3 years - 42. All because of upgrades
Ive been more patient recently, I have no choice as I bought a house and Im going to have to watch how I spend.
Ill upgrade a older disc for a newer version, like Goodfellas and Born On The Fourth. Im not much for features, so usually the barebones version will do me just fine - though for films like Hellboy or Spidey2, I do enjoy the "Making Of" features.
"I have NEVER bought a movie that I didn't plan on watching multiple times. If a movie doesn't have rewatchability I wouldn't buy it."
Id say 80% of my collection is essential while 20% is stuff I could do without. Ive bought DVD blind,but only ones that come with glowing recommendations from someone like James Berardinelli, who I think has great taste in film.I think I bought maybe 10 DVDs blind I wasnt happy with. Not too bad.
I will also go thru my collection once a year or so and ebay off or give away the stuff I think is just taking up space.