There is a type of commercial I’ve learned to be suspicious of. The product always is supposed to solve a real life problem with amazing wonderfulness. They always offer a second one free or for a nominal price, “just pay an additional handling charge.”
After seeing the commercial for Zap! for the umpteenth time and wondering if it would clean the grout in my floor, I Googled “Zap! complaints.” The first result was a link to where it is sold on Amazon (not solely online as they claim). Here are the reviews:
Most said it was no more effective than any other ordinary cleaning product, and was not effective on grout.
When in doubt, Google it.