I recently bought a 740b, which gets AHRS information from a Stratus 3. I like the screen brightness of the 740b and intuitive iFly interface. However I am curious why there is a setting to select synthtic vision rendering speed. Even set to the fastest rendering speed, the horizon on the 740b is noticeably slower to react to attitude changes than my iPhone 6 running the Stratus Horizon Pro app. The processor in the 740b generally seems rather slow, for example it takes 2+ minutes to boot up (compared to under 10 seconds for iFly to launch on the iPhone).
Why would you want to set rendering speed to anything other than "fastest?"