I have subscribed to Quickflix, which is a DVD rental program in which you select the DVDs you want through the Internet and Quickflix send it to you via mail (see How it Works). When you've watch the DVD, you return it back via mail as well and then when Quickflix gets its DVDs back it sends you more from the list you made.
I have three criticisms of this. The first is that putting DVDs in the mail isn't that much of an improvement over returning DVDs to the video store. You still have to drive to the post box and that is an inconvenience. In my case, the nearest post box with a car park nearby is in a shopping center and in this shopping center there is already a video store. It therefore makes no difference whether I return a DVD at a video store or a post box because the two are right next to each other. What would be an improvement is having a delivery person personally go to your house and pick up the DVDs, which you leave outside the front door. Of course, if this were to happen then the DVDs would be more expensive to cover the wages of the delivery driver, and I doubt many customers will want to pay more. When I return or get DVDs I simply drop by the video store or post box on the way to uni or from uni to home.
The second criticism is that DVD by mail forces you to watch the movie quickly. When customers pay for gym membership they usually prefer to pay one flat fee and use the equipment as much as they choose. E.g. they're rather pay $20 per month instead of $1 per minute. The reason why this is the case is because many customers don't want to think that the clock is ticking and that they have to be conscious how much time they are taking. They just want to take their time and not worry that their lazy behavior is costing them more. The problem with DVD by mail is that when you get the DVD you have to watch it quickly and return it. If you don't watch it quickly and return it as soon as possible then since you are paying by the month (e.g. $30 a month) then you won't watch many DVDs per month which is not cost efficient in terms of trying to get the most DVDs for the amount you pay. The clock is ticking. When you go to the video store, usually you have one week to watch the movie. If you return the DVDs early you get no benefits at all, so this makes you feel relaxed because one week is usually a long time. Some movies are overnight rentals but most I get have to be returned in a week.
The third criticism I will give is just one I have recently thought of. Other providers may be different but I am talking about Quickflix in particular here. I want to say that it is expensive. Looking at its subscription plans and prices, although it is kind of cheap depending on how fast you watch the movies, it doesn't beat Network Video's $1 DVD hire on Tuesdays. However, one of the problems with Network Video's $1 DVD hire on Tuesdays is that usually when I want to watch my favorite movies I find it's all taken. At least with Quickflix I can put it on a queue and they find it for me instead of me having to find it myself.