I Never had the urge to use one. I have on occassion used a paring knive to strip kernals off the cob, but being a mid-western hick, I still enjoy corn straight off (or still on ) the cob.
My FIL has all kinds of bridges and stuff, so he won't eat it off the cob, uses a butter knife to strip it off, but Tough Sh1t sherlock.
MIL still chomps a mean cob at 84 years old.
Got any pix to post. I'm not familiar with these devices.