As you know in Windows 8.1 you can use Shift + Restart combination to disable driver signature enforcement. But the problem is this is not a permanent way for disabling... Every time you must do that.
I have read that the following commands can do permanently:
bcdedit -set loadoptions DISABLE_INTEGRITY_CHECKS
bcdedit -set TESTSIGNING ON
Having tested the above commands. Although after restarting windows I see a watermark that I'm in Test Mode but I would not able to install my unsigned driver. I am able to install my unsigned driver by shift + restart way only.

First, do those commands still work on Windows 8.1 64bit?
Second, what would you recommend to disable driver signature enforcement permanently?