I've been meaning to do this for...some time now. I can't remember how long. That's how long it's been.
Here's a little comparison for you - not that I like to compare!
|Top: Maybelline Gel Liner in Black|
Bottom: Physician's Formula Shimmer Strip for Brown Eyes Black Gel Liner
|Smudge test after 15 minutes. PF wins =P|
I can't compare to MAC Fluidline or Bobbi Brown's gel liner because...I haven't tried either of them. You can flog me.