I bought this card to use with my Nikon D40 as I wanted a 'premium' card to use with my first DLSR. The write-read times seem to be pretty good, I can shoot continuously with only a seconds delay, although I'm not sure how much of this time is the actual camera processing.
The main feature of this card is the ability to fold the bottom part of the card up, as you do this, a very thin USB connector pops out. I did find this connector to be a bit of a squeeze when using it with the USB port on my MacBook, but it works perfectly and doesn't seem to have damaged anything, although I did make two scratches on it when I first got it, trying to jam it in the USB port the wrong way round!
The quality of the product seems to be pretty sound. The hinge looks quite delicate and fiddly but mine has been absolutely fine so far, and I must of clicked it in and out thousands of times. I did find that the card still flexed slightly even when the usb was in the 'locked' position but it doesn't seem to have caused any problems.
What I really like about this card is the ability to use just like a USB thumb drive, due to its built in USB connector. It's also much smaller and thinner than most USB drives around, and comes in a small plastic case, to keep it safe when transporting. Overall a great idea, saves a lot of hassle when you know you can transfer your pictures to any computer with a USB port.