I'd be happy to buy an issue at a time - I think $.5 would be a fair price given that there is no printing cost and that the advertising is more valuable as it's micro targeted to me. I'd buy an issue to read a particular article or because I want one to read for general amusement.

Subscription feels like monogamy, I've got lots of different things to spend cash on, I don't want to commit at this scale to spending it on things I may not want.