We went in the store and I started loading the kids in the cart when I noticed the "fun carts" and thought it was definitely worth a try. These tv carts had a choice of Barney or Bob the Builder so I chose the latter, paid my dollar, buckled the kids in, made sure the show started, closed the doors and locked them, and started shopping. They loved it! They were obedient, quiet, and most of all they got along. They couldn't get out and run around, I didn't have any "extra" things in my cart, and we made it through without any meltdowns.
This was a dollar well spent and I will definitely consider using it again when I need to shop with both boys. We all came out of the store with smiles (even with it being way past lunch time)!
*This picture is of a similar cart - we did not do Barney!*