SD Card Recommendations?
 

I notice that Sandisk has 128 GB SD Extreme cards, class 10 with speeds "up to" (whatever that means) 45MB/s.

They also have an Extreme Pro class 10 version with speeds to 95MB/s, but only up to 64 GB's in capacity.

Will there be any practical benefit to a faster speed card? Is 128GB's overkill? I am not sure how many minutes 128 will handle, but I can't imagine filming days and not downloading each evening to ensure no catastrophic footage loss if a card corrupts.

Re: SD Card Recommendations?
 

The practical effect of faster card read speeds is quicker loading of footage onto your computer.
The practical effect of faster card write speeds is more flexibility in cameras. If all your handling is 25 - 72 Mbps, that translates to 3.25 - 9.75 MB/sec. which a Class 10 card should handle nicely. But if there is something like the Black Magic Pocket Cinema Camera in your near future, which I believe shoots 220 Mbps / 28 MB/sec. ProRes, then you are going to need something considerably quicker. Same applies for any of the consumer Canon DSLR cameras shooting RAW with Magic Lantern.

Hope this helps.

If your handling 25 Mbps footage then a 128 GB card can hold about 11 hours of footage.

I have a mess of 32 GB cards and a few 64 GB cards. It's worked for me so far. YMMV.

Re: SD Card Recommendations?
 

I've been having great luck with these cards: Samsung Electronics 32GB Pro Extreme Speed (UHS-1) Class 10. Although I haven't hit the advertised "Up to 80MB/s read (UHS-I Interface), Up to 40MB/s write (UHS-I Interface)" I was getting about double the speed of my other class 10 cards. The sub $30 price is hard to beat.

I would be concerned about 64/128GB getting corrupted, so I'll stick with 32GB for now. 187min. of AVCHD footage on 1 card is already risky. (I do wish there were a 2nd card slot instead of the FMU unit).

Re: SD Card Recommendations?
 

I remember when I worried about the 32 gigs getting corrupted. I went out and bought 4 of them that have been in service for 3 years now. Now I worry about the 64 gig. so I went out and purchased 2 of those. Just finished a 4 day shoot with at least 40 hours of footage. Worked like a charm but it still worries me. I will not be deterred by worry.

I only use Sandisk as I worry about other brands.

Re: SD Card Recommendations?
 

Just remember that if you want those faster download speeds, you need either a USB3 or the UHS-I ExpressCard reader from Sonnet (I use it in my 17", but with the Echo Pro Express you can use Thunderbolt to basically pull it off the card as fast as the laws of physics allow!).

If you only have a USB2 reader (or the built-in reader on a laptop, monitor, ect.) then more normal Class 6 and above cards will saturate that bandwidth.