I read some post of a photographer saying he always keeps 2 cards. One he uses and the another card as a spare card. He said that if a card gets ruined, wet, damaged it is best to have another one ready. Having a large size card 'lets' you store too much pictures on it, and if it gets ruined you lose more pictures. When having 2 smaller size cards, then you must switch them or empty them down to your computer more often. Is he right ? anyone here uses more than one card per camera ?