>> My rural internet connection is 40mbps/sec down in theory — in practice it’s between 25 and 40 depending which second you poll it, and the speed is affected by whether someone is downstairs watching Netflix while I’m upstairs playing a graphics-intensive game.

I'm surprised he even bothered trying the service let alone he found it playable. A rural area with 25-40mbps with someone using the internet at the same time ( let alone netflix!) is basically worst case scenario. If you are playing near a datacenter with reasonable internet your experience will be significantly better. Geforce now is technically very good when configured properly; it is similar to parsec (which is probably state of the art).

Worth pointing out: the Geforce now library is not great and and I wouldn't hold my breath on it improving too much. Most interested publishers have already signed up and the rest are either commited to other platforms or aren't willing to choose nvidia over other monetization options.