For any movie I care about, I just buy the Blu-Ray disc or DVD. There are of course the obvious enhancements to video and sound quality, and also the fact that I automatically have a digital copy right there (think of ordering the disc as simply initiating a download that takes a couple of days to complete- or an hour if you go to the store to get it- and comes with an offline backup copy already made for you). More importantly, I do not desire to hitch the continued existence of my purchases to the continued success of any particular corporation. When, say, Amazon, or any of their competitors, goes out of business 10 years hence, and 40 million people lose their entire "purchased" movie, book, and music libraries, I don't care to be one of them.