I found the swiping response also to be less reliable than on recent smartphones or tablets. For me it works best when I don’t swipe from the very edge but start somewhere below the center of the screen when swiping up or above the center of the screen when swiping down. And it actually works better for me when not swiping fast but at a moderate speed. Somewhat contradictive to the other statements and reccomendations above but that’s how it works best in my case.
EDIT: consider voting for this feature: Activate / Deactivate Gigview via foot switches (even with locked touchscreen)