I have had Card Errors with only Sandisc, both 2g and 4g cards. Sandisc has replaced the cards (6 cards) twice now and they still give me the Card Err warning. I have been staying away from Sandisc becauce of the Card Err and because of lost shows where the card looked to be working fine but was not. I'm using Lexar 2g 133x, Kingston Elite 2g 80x, PNY 2g and Ridata 2g 80x without any issues at all.