Postscript: To ensure colour profiles persist across reboots, you have to do one more thing by clicking on one more checkbox in the poorly laid out Color Management module, "Use Windows display calibration". This link has a good series of screenshots with the relevant items circled: Load profiles in Windows
I also do one more thing in addition, on the advanced tab in the beginning on the Windows Color System Defaults for Device Profile, I also change that to match the same one as selected on the Devices tab. This is for non-color managed stuff, but honestly, the difference is so small from sRGB you can consider this optional. Color managed apps won't be paying attention to this but just the Devices tab. Remember to reboot the computer.
Gradients test on lagom is fine to compare between different profiles. You will likely see differences between some. Perhaps banding (delete those profiles), or too much grey or whatever. The ideal balance is that the dividing line is at the 50% mark.