The undercut would be a better modification for me. The Glock knuckle sucks but I also feel like my fingers are really cramped when gripping this pistol.

I don't really need every thing on the Hatfield package but they don't list prices of individual modifications. The grip on the Gen4 19 is fine in terms of grippyness.

I like the idea of using the dowel because I can go slow and see what happens. I might stop by Hatfields one day to see if they have any examples I can hold of their modded glocks.