Overall, the tested lithium batteries performed much better than the alkalines ... Battery life was 7.3 hours for an Energizer, 6.8 hours for a Duracell, and 4 hours for a Toys "R" Us battery.

There’s an interesting story where Duracell had used the bunny for years in europe, only to inspire Energizer to copy them stateside in 1989. This one will be available on ebay shortly.