Summary: Before buying this card check with others if it's compatible with what you will be using. I've never had an issue like this before with a CF card. It works perfectly fine in my old Canon Rebel XT so I will be using it for that. But it would be nice for my beloved to have another card.
Pros: I liked the cost of this card and it certainly seems to work in my rebel XT. I can see the card on my PC and a Mac with a regular card reader.
Cons: I bought it for my finance's new D300S and it seems to register on the card and I can format it. The problem is any picture taken is all black (R=0, B=0, G=0). The Nikon D300S just does not like this card.
Summary: The performance of this supposed 400x card seemed slow so I RMA'd to Transcend. The card I got back does seem faster, but is definitely not faster than a 200x card I have from another manufacturer. Then I read the fine print on the Transcend website - the 8GB and 16GB 400x card are only a max of 30MB/s - that's 200x. I could have sworn Newegg's desciption had said 90MB/s read and 60MB/s write, but Newegg has since corrected their description.
Pros: Seems to work well. Decent performance for the price. See other thoughts.
Cons: Shouldn't really be marketed as a 400x card. 30MB/s max write is 200x. See other thoughts.
Summary: Despite my cons, running a benchmark (atto) on this card through my card reader shows that it is faster than the 200x card. That's what makes me say the jury is still out. (BTW - I love my Hoodman UDMA reader - wish Newegg sold those!
Pros: Big and affordable. Works OK in my 7D.
Cons: I'm using this card in a Canon 7D. Other reviewers say "works great" but I'm not sure what they're comparing to. This card appears to be a bit slower than my Sandisk Extreme III (a 200x card), which seems to match up with another reviewers analysis that these are somehow really 133x cards. I can only shoot 20 RAW pics in a row if I'm lucky. 6-8 is more an average case.
Summary: Habe gleich mal die "große" 64 Gb Karte genommen obwohl ich mir nicht sicher war ob die 400X reicht für Serienbilder mit der Canon EOS 7D. Habe dann bei einem Shooting ca 6000 Jpegs geschossen und einige Filmaufnahmen gemacht dann auch Raws. Es war ein perverses Dauerfeuer geballer vom allerfeinsten.
Summary: habe 2 Stück 64 GB Karten vor gut einem Jahr gekauft, leider lässt sich die erste Karte jetzt weder formatieren noch kann mann neue Fotos machen, die zweite Karte beginnt auch zu spinnen. Habe jetzt die erste Karte zum Händler geschickt mal sehe was passiert. Zuverlässig sind die Karten aber nicht. Für wichtige Aufträge unbrauchbar, da man nicht weiß ob sie vor Ort funktionieren.