I'm really surprised to hear that the slow restore times from tarsnap are still as big a problem now as they were a decade ago when I last used it. I absolutely loved the interface and the security model, and I was willing to pay at the (very) premium price point, but it was just too impractical trying to restore anything from it at the speeds I could achieve. (If I remember right, there was some problem with the design which meant normal latency between the client and the server tanked throughput to crazily low levels.)