There is no double nat. Passthrough mode has worked as expected for me. The one issue I have is that the RG will maintain firewall states, so it limits you to the RG hardware for those states. I have a pretty large home network though, tons of devices, IoT, etc, and it has been stable.
Latency seems decent. I have an AT&T fiber 2gb symmetrical connection and a ping to google from my Netgate pfSense machine is around 10-15ms.
I was wondering the same thing. Maybe in the USA it is easier due to our relaxed (almost non-existent) business oversight from the government? Not sure.