So far I use Highspeed for focusing. There is definitive a difference you can experience in download time. So highspeed is working with the camera and SGPRo, but not through the API. It's like the population of the FITs headers, which is different (degraded) in comparison to the program when using through the API.
THe more I am using SGPRo through the API the more differences I find. It's a little bit disappointing for that great software showing degraded features for the same functions working really nicely from the program GUI.
Michel