I was thinking about going prgmr. But it took them ~ a month to install more servers and re-open signups. Yes, they're cheap. But I wouldnt trust them for anything production-stage. What if their server fails? Will they replace parts in 1 hour? I think GitHub is much more reliable in this case...
I'm not on prgmr yet but I've heard good things. And Backblaze is awesome.