I had been using SanDisk Extreme III (30 MB/s) in my Nikon digital SLR, and while they were reliable and so on, I was never able to get the full high speed frame rate Nikon promises. Instead of the 5-7 frames per second, I was getting more like 2-3.

Switching to the 60MB/s fixed that problem, and now I'm getting the full performance my camera is capable of...at least 5 fps under most conditions.

Interestingly, I also purchased a smaller card capable of 90MB/s, and saw no real difference, so I'm considering the 60MB/s version ideal - nice, since it's much less expensive than the faster cards.

Recommended if you need the best frame rate out of your camera.