From what I've read there are no worries about G forces from this engine. The key is there is (usable?) acceleration where theory says there shouldn't be any. The Dawn space probe could go from 0-60 MPH in four days, which is ridiculously slow acceleration. Because of that small acceleration though, it's the only probe to ever orbit two extra-terrestrial bodies.
The real health/safety issue with low grade propulsion isn't speed, it's lack of speed. For example, I read an analysis of the space elevator concept that said the radiation in the Van Allen belts is so high that unshielded passengers wouldn't survive the trip. The moon astronauts were only exposed for a short time because they were riding a much quicker Saturn V.
Mike, I agree. Even if it couldn't be used for launch, I could see orbiting space tugs to ferry payloads to various destinations. Even better, since it's a closed system physically they could run indefinitely on solar power. It would enable some really cool missions, too. Anything not too deep in a gravity well is fair game. How about a sample return from Saturn's rings?
(found the radiation article-
https://www.newscientist.com/article/dn10520-space-elevators-first-floor-deadly-radiation/)
