My Minewxt X2 Dual is very very bright on flash mode, so I only use it on the streets, not the MUP, and even then I tend to run it on steady/high when it's fully dark.

2 weeks ago on my ride home a woman (after she nearly right hooked me, with no blinker, natch) kept stopping in front of me, and finally yelled at me that my light was too bright and it was the most dangerous thing she'd ever seen, and was going to kill someone. I told her that she was in a car, and if she just drove instead of continually slamming on her brakes, she'd be a mile away by now and my light wouldn't have been an issue.