Hi Y'all! Here is the comparison I promised earlier this week. I just got in the Blue Skies Stamp Set by Lawn Fawn, so I thought it would be fun to use for the bake-off. I DID NOT try to do expert coloring and blending. What I wanted to do was to completely saturate the paper with the most difficult color to use - RED. And, see what happened. I SOAKED this paper, and I mean soaked! On the left is Memento and on the Right is Gina K.
My final opinion is that the Gina K black is a darker more true Black and it did NOT smear at all - I love it!! I did however let it dry for an hour (broke for lunch). Use it wet, and it will smear. Memento is tried and true. It won't smear no matter what, but the black is a bit dull. Either are perfect for Copics, as long as you let the Gina K ink dry completely. My pick: Gina K.
Good luck to you! Let me know how they work for you.