Summary: What the other reviewers said is spot on - if you need a ton of space and don't mind slow write times, this card is great. You can't beat the price for 16GB. The write times are definitely slow - I am shooting with a 5D (the original, not the Mark II), and I really noticed it. It isn't an issue for me - I don't generally shoot in bursts of more than a few shots, but if you are a machine-gun style shooter, you will definitely hit the ceiling on this card.
Summary: i like it cus of its amazing space but its kind of slow on my camera... i shoot a d300 and it makes the live view slow when i use this card and reviewing pictures takes along time.. also it some times freezes while shooting and im scared if the card going bad..
Summary: Yeah, this card holds a lot and you can shoot to your heart's content, but its mighty slow in RAW, with serious drag between shots and slow review time. If you shoot hard on the fly I really wouldn't recommend this card. If you're a casual snap-shot shooter you'll love it. Canon 40D user.
Summary: I bought several of these cards. They have really great speed until you put 800-1000 raw pics on them. Then they slow down to and unbearable crawl. I find myself just removing them and putting in a new one. If speed is no issue then this card is for you... Otherwise I would not recommend.