Do you mean the Baby Einstein cards? We have both those and the Eric Carle set. The Eric Carle set is sturdier but the Baby Einstein cards are still laminated cardboard so they will hold up decently well. DS2 will look at the cards occasionally, but they are definitely not a favorite. He's learning most of his animals from books.
Sortfloorbooks has the Eric Carle set for cheap.
http://www.sortfloorbooks.com/?page=...25e3b2a696670b
One way to choose is do you prefer actual photographs of animals or illustrations?
Mommy to 2 DS's (2003 and 2007)