Best controller I have ever used. EXTREMELY accurate. These are the best settings that I have found and how to change them in the Flydigi Space Station app.
1. Plug in your Flysync dongle as well as your Vader 4 Pro via the provided cable.
2. Download Flydigi Space Station from the Flydigi website and install it.
3. After booting it up click on the cog wheel in the top right corner, click on settings, click on language and select the installation language as the top most language (looks like this 简体中文). Once the app boots up in Chinese you can update the controller and dongle (sometimes it will even update the app to a new version that hasn't made it to western countries yet).
4. Click on the cog wheel in the top right corner. Click on settings (looks like this 设置 with a cog wheel in front of it), click on language (it's the middle selection that has this 语言 with two other symbols in front of it), change the language to English in the drop down menu. App will restart in English.
5. In the "PC Config" go to each of the 4 profiles go to "Joystick" Set the "Joystick Center" to 4 (I found this setting the best deadzone value to avoid stick drift in games), scroll down and change "Circularity Algorithm" from Rectangle to Circle if you want perfect circularity. However, I prefer Rectangle due to less processing and snappier target acquisition (make sure to do all of these steps in all 4 profiles or at least for the ones you intend to use).
6. Click on "Function Settings" in the lower left corner of the app. Activate the "Quick Switch Configuration" toggle (allows you to change through the 4 profiles without the app by simply holding "select+a or select+b or select+x or select+y") toggle OFF Joystick Debounce, change Joystick Accuracy to 12 bit, make sure Joystick Polling Rate is set to 1000Hz, change Joystick Center Sensitivity from Middle to Fast. Congratulations, you are done!
I sincerely hope this helps everyone. I tried to be as descriptive as possible with the steps. I have found the Flydigi Vader 4 Pro to be by FAR the most accurate controller I have every tested after changing the above settings. Enjoy!