I've searched the Hog for recent posts on this topic, but there isn't anything recent on the topic of SD card speed and capacity. Several links in the pinned topic on the subject are broken, so I'm asking for advice here.

I have a Nikon D7100, which will take both the SDHC and SDXC cards, according to the manual. I currently have Sandisk 32Gig SDHC cards with the "3 in a box" mark, which I assume indicates Class 3. When shooting RAW in burst mode, I find that the camera is not shooting at the rated 6 FPS burst speed, and I'd like to be able to take advantage of it for some of our grandkids' school sports. The online buyers' guides I've found are sometimes conflicting or contradictory in their advice. For example, the Best Buy online guide suggests a 3 class card is sufficient for burst shooting of RAW images, which it really isn't, at least from my experience. The B&H guide is slightly more helpful, but it doesn't even show a 3 class 32G SDHC card in its list.

So my twofold question:

1) Will I need to go to SDXC or just a higher "class" SDHC card to achieve 6 FPS for more than a couple of seconds at a time?

2) Is there a good online guide to buying SD cards for various types of photography? I haven't really been enthusiastic over the ones I've found.

Thanks in advance for any advice or insight. It was easier picking film!

Andy