Shutter precision SV9 is even lighter than the PV8. But SV9 is designed for small wheels, so puts out a little less power in a 700C wheel.
This may or may not be an issue. I have an old SON 20 hub designed for 16"/20" wheels on my old 700C tourer, it works perfectly well with modern LED front and rear lamps.
Wife has a Shimano DH-3N80 on her bike - very free running and I reckon a good quality/price compromise for a lightweight bike mainly used on road.
I have an SV8 on my commuting Brompton folder and a SON on my older Brompton used for some tours. SV8 is small and light like the competing SON, seems to work just as well. I chose SP because the only Shimano hub that would fit the narrow Brompton forks is a low-range model that I suspect (maybe wrongly) would be less efficient.
The only issue I can see between SP and SON is that if the SP goes wrong it will be harder to get it repaired. SON you can send back to the factory in Germany, more difficult to do this with SP. The bearing on one side of a Shimano DH-3 series hub is easy to service at home, I think it is possible to do the other side with care, but so far I haven't needed to.
SP claim higher efficiency than SON, but I can't tell the difference between SP, SON or Shimano DH-3N72/DH-3N80 when riding.
Older entry-level Shimano dynohubs were noticeably less efficient than SON, which is why I bought SON hubs until a few years ago, but the more recent DH-3N7x and upwards seem to come pretty close to SON.
So far (touch wood) I've not had any issues with any of the family's dynohubs, whether SON, SP or Shimano.